BASEBALL THROWING MECHANICS AS THEY RELATE TO PATHOLOGY AND PERFORMANCE - A REVIEW

Directory of Open Access Journals (Sweden)

Rod Whiteley

2007-03-01

Full Text Available It is a commonly held perception amongst biomechanists, sports medicine practitioners, baseball coaches and players, that an individual baseball player's style of throwing or pitching influences their performance and susceptibility to injury. With the results of a series of focus groups with baseball managers and pitching coaches in mind, the available scientific literature was reviewed regarding the contribution of individual aspects of pitching and throwing mechanics to potential for injury and performance. After a discussion of the limitations of kinematic and kinetic analyses, the individual aspects of pitching mechanics are discussed under arbitrary headings: Foot position at stride foot contact; Elbow flexion; Arm rotation; Arm horizontal abduction; Arm abduction; Lead knee position; Pelvic orientation; Deceleration-phase related issues; Curveballs; and Teaching throwing mechanics. In general, popular opinion of baseball coaching staff was found to be largely in concordance with the scientific investigations of biomechanists with several notable exceptions. Some difficulties are identified with the practical implementation of analyzing throwing mechanics in the field by pitching coaches, and with some unquantified aspects of scientific analyses

Reviews of large superconducting machines: Metallurgy, fabrication, and applications

International Nuclear Information System (INIS)

Bogner, G.

1981-01-01

This paper reviews large superconducting machines presently in place or in experiment. The ''Cello'' particle detector magnet for the positron-electron colliding beam facility PETRA at DESY in Hamburg is shown, and the Fermi Lab, and the Brookhaven ISABELLE also described. Electrodynamic levitation systems are specified, as researched and developed in Germany and Japan. Of superconducting coils for magnetic separation, a high gradient magnetic separator with superconducting magnet and steel wool, and a Jones type high gradient magnetic separator are schematicized. Turbogenerators with superconductor field winding are studied. Superconducting high power cables include the flexible coaxial cable core consisting of a perforated polyethylene tube and test cables at Siemens and at Brookhaven. Magnet systems for fusion reactors include tokamaks and tandem mirrors, and the toroidal coil experiment at Oak Ridge National Laboratory is described, among others. Superconducting magnets for MHD plants, and superconducting magnet energy storage (SME storage) are also discussed

Baseball and softball injuries.

Science.gov (United States)

Wang, Quincy

2006-05-01

Baseball and softball injuries can be a result of both acute and overuse injuries. Soft tissue injuries include contusions, abrasions, and lacerations. Return to play is allowed when risk of further injury is minimized. Common shoulder injuries include those to the rotator cuff, biceps tendon, and glenoid labrum. Elbow injuries are common in baseball and softball and include medial epicondylitis, ulnar collateral ligament injury, and osteochondritis dissecans. Typically conservative treatment with relative rest, medication, and a rehabilitation program will allow return to play. Surgical intervention may be needed for certain injuries or conservative treatment failure.

Large superconducting magnet systems for plasma and fusion applications

International Nuclear Information System (INIS)

Heinz, W.

1976-05-01

Work on superconducting magnet systems and state of the art of superconducting magnet technology are described. Conceptual design consideration and problems of large magnet systems (stability, magnetic forces, cooling modes, safety) are discussed. Recent results of experimental work at Karlsruhe are reported. An outline of American and European programs is given. (orig.) [de

Effects of neuromuscular joint facilitation on baseball pitching velocity and electromechanical reaction times of the teres major of young amateur baseball players.

Science.gov (United States)

Wu, Peng; Huo, Ming; Maruyama, Hitoshi

2013-11-01

[Purpose] The aim of this study was to investigate the changes of baseball pitching velocity and electromechanical reaction times (EMG-RT) of the teres major of young amateur baseball players after neuromuscular joint facilitation (NJF) treatment. [Subjects] The subjects were 18 healthy males who were divided into two groups: a NJF group and a control group. The NJF group consisted of 10 subjects, and the control group consisted of 8 subjects. [Methods] Participants in the NJF group received NJF treatment. The baseball pitching velocity, the EMG-RT, the premotor time (PMT), and the motor time (MT) during shoulder internal rotation movement were measured before and after 8 weeks of exercise. [Results] There were no significant differences among the results of the control group. In the NJF group, there were significant differences in baseball pitching velocity, EMG-RT and MT after NJF treatment. [Conclusion] NJF intervention shortens not only EMG-RT but also MT, which implies that NJF is effective for motor processes. Since the baseball pitching velocity increased, NJF may be recommended for the improvement of the performance of baseball players.

Stability of superconducting cables for use in large magnet systems

International Nuclear Information System (INIS)

Tateishi, Hiroshi; Schmidt, C.

1992-01-01

The construction of large superconducting magnets requires the development of complicated conductor types, which can fulfill the specific requirements of different types of magnets. A rather hard boundary condition for large magnets is the presence of fast changing magnetic fields. In the Institute of Technical Physics of the Karlsruhe Nuclear Research Center, Germany, a superconducting cable was developed for use in poloidal field coils in Tokamak experiments. This 'POLO'-cable exhibits low losses in a magnetic ac-field and a high stability margin. In the present article the requirements on a superconducting cable are described, as well as the mechanisms of ac-losses and the calculation of the stability limit. Calculated values are compared with experimental data. Some unresolved problems concerning the stability of large magnets are discussed taking the example of the POLO-cable. (author)

Hamstring Injuries in Major and Minor League Baseball

OpenAIRE

Zachazewski, James; Silvers, Holly J.; Li, Bernard; Snyder-Mackler, Lynn; Insler, Stephanie; Ahmad, Christopher S.; Mandelbaum, Bert R.

2016-01-01

Objectives: The purpose of this study is to test the efficacy of a hamstring injury prevention program designed to address the high incidence of acute and chronic hamstring injuries and re-injuries that occur in the sport of professional baseball. Methods: This was a prospective cluster cohort study assessing the efficacy of an injury prevention intervention designed to address hamstring injury in rookie and professional baseball players participating in Minor and Major League Baseball (N = 2...

Design and manufacture of a large superconducting homopolar motor (and status of superconducting a.c. generator)

International Nuclear Information System (INIS)

Appleton, A.D.

1983-01-01

This paper describes the design and manufacture of a large superconducting motor which, in the present time of financial restraints, is continuing at least to the point of having a completed cryostat with its superconducting winding operating with a dedicated helium refrigeration plant. Comments are also made on the superconducting a.c. generator project, although a final decision on the rating of a prototype and the approval of the funding has not yet been made, the selected rating is expected to be between 200 MW and 600 MW

Going, Going, Gone! The Making of a Baseball Bat

Science.gov (United States)

Cantu, Diana

2012-01-01

From little league players to professional athletes, baseball has become a sport that is not only fun to play and watch, but also a sport driven by innovation and technology. One particular piece of baseball equipment that has undergone many changes is the baseball bat. Prior to the early 1970s, wooden bats were the only choice available. Today,…

Little League Baseball and Players' Self-Esteem.

Science.gov (United States)

Hawkins, Donna B.; Gruber, Joseph J.

1982-01-01

The effect of a season of little league baseball on the self-esteem of 94 pre-adolescent players was investigated. The Coopersmith Self-esteem Inventory and a newly devised Baseball-Self scale were administered. Significant improvements in players' total Self-esteem, Home-Parents and School-Academic scores were found. (Author/PN)

Changes in Cuba’s Migration Policy and Its Impact on Baseball

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Onesimo Julian Moreira Seijos

2014-11-01

Full Text Available Baseball is an essential constituent of the Cuban national identity. For nearly a century, Cuban baseball players had joined high-ranking international leagues, including the Negro Leagues and Major League Baseball (MLB of the United States. After the triumph of the Revolution in 1959, the professional practice of sport was banned in the country. On the other hand, the revolutionary government instituted migration rules that disallowed Cuban citizens to travel abroad freely. Until the collapse of the Soviet Union, the Cuban national baseball team reigned in amateur competitions worldwide. Sporting successes in general and those of baseball in particular, were managed by the government as a political tool; the government used to display the loyalty of the athletes as a triumph of the Cuban system. However, since the nineties there has been a growing departure of Cuban top baseball players who have had the target of entering in MLB franchises, disregarding that the Cuban migration policy had remained unwavering. On the other hand, after the enactment of changes in the Cuban migration policy in 2013, the unconventional departure of high performance baseball players has increased sharply. The relationship between the migration reform and the increased leakage of baseball players has not been studied by scholars. The relevance of this paper is that it is the first academic approach to that relationship. This paper discusses the migration reform in Cuba and focuses mainly on its impact on baseball.

Visual-Motor Control in Baseball Batting

Directory of Open Access Journals (Sweden)

Rob Gray

2011-05-01

Full Text Available With margins for error of a few milliseconds and fractions of an inch it is not surprising that hitting a baseball is considered to be one of the most difficult acts in all of sports. We have been investigating this challenging behavior using a virtual baseball batting setup in which simulations of an approaching ball, pitcher, and field are combined with real-time recording of bat and limb movements. I will present evidence that baseball batting involves variable pre-programmed control in which the swing direction and movement time (MT are set prior to the initiation of the action but can take different values from swing-to-swing. This programming process utilizes both advance information (pitch history and count and optical information picked-up very early in the ball's flight (ball time to contact TTC and rotation direction. The pre-programmed value of MT is used to determine a critical value of TTC for swing initiation. Finally, because a baseball swing is an action that is occasionally interrupted online (i.e., a “check swing”, I will discuss experiments that examine when this pre-programmed action can be stopped and the sources of optical information that trigger stopping.

Early Sport Specialization: Effectiveness and Risk of Injury in Professional Baseball Players.

Science.gov (United States)

Wilhelm, Andrew; Choi, Changryol; Deitch, John

2017-09-01

The rate of early sport specialization in professional baseball players is unknown. To report the incidence and age of sport specialization in current professional baseball players and the impact of early specialization on the frequency of serious injuries sustained during the players' careers. We also queried participants about when serious injuries occurred, the players' current position on the field, and their opinions regarding the need for young athletes to specialize early to play at the professional level. Descriptive epidemiological study. A total of 102 current professional baseball players anonymously completed a 7-question written survey. Early sport specialization was defined as "single-sport participation prior to high school." Injury was defined as "a serious injury or surgery that required the player to refrain from sports (baseball) for an entire year." Chi-square tests were used to investigate the risk of injury in those who specialized early in baseball versus those who did not. Independent-sample t tests were used to compare injury rates based on current player position. Fifty (48%) baseball players specialized early. The mean age at initiation of sport specialization was 8.91 years (SD, 3.7 years). Those who specialized early reported more serious injuries (mean, 0.54; SD, 0.838) during their professional baseball career than those who did not (mean, 0.23; SD, 0.425) ( P = .044). Finally, 63.4% of the queried players believed that early sport specialization was not required to play professional baseball. Our study demonstrated a statistically significant higher rate of serious injury during a baseball player's professional career in those players who specialized early. Most current professional baseball players surveyed believed that sport specialization was not required prior to high school to master the skills needed to play at the professional level. Our findings demonstrate an increased incidence of serious injuries in professional baseball

Hip and Groin Injuries in Baseball Players.

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Mlynarek, Ryan A; Coleman, Struan H

2018-03-01

To discuss the clinical significance of the most common hip and groin injuries in baseball players, as well as an algorithmic approach to diagnosis and treatment of these injuries. (a) Limitations in throwing velocity, pitch control, and bat swing speed may be secondary to decreased mobility and strength within the proximal kinetic chain, which must harness power from the lower extremities and core. (b) Approximately 5.5% of all baseball injuries per year involve the hip/groin and may lead to a significant amount of time spent on the disabled list. Injuries involving the hip and groin are relatively common in baseball players. Our knowledge of the mechanics of overhead throwing continues to evolve, as does our understanding of the contribution of power from the lower extremities and core. It is paramount that the team physician be able to accurately diagnose and treat injuries involving the hip/groin, as they may lead to significant disability and inability to return to elite levels of play. This review focuses on hip- and groin-related injuries in the baseball player, including femoroacetabular impingement, core muscle injury, and osteitis pubis.

A superconducting large-angle magnetic suspension. Final report

International Nuclear Information System (INIS)

Downer, J.R.; Anastas, G.V. Jr.; Bushko, D.A.; Flynn, F.J.; Goldie, J.H.; Gondhalekar, V.; Hawkey, T.J.; Hockney, R.L.; Torti, R.P.

1992-12-01

SatCon Technology Corporation has completed a Small Business Innovation Research (SBIR) Phase 2 program to develop a Superconducting Large-Angle Magnetic Suspension (LAMS) for the NASA Langley Research Center. The Superconducting LAMS was a hardware demonstration of the control technology required to develop an advanced momentum exchange effector. The Phase 2 research was directed toward the demonstration for the key technology required for the advanced concept CMG, the controller. The Phase 2 hardware consists of a superconducting solenoid ('source coils') suspended within an array of nonsuperconducting coils ('control coils'), a five-degree-of-freedom positioning sensing system, switching power amplifiers, and a digital control system. The results demonstrated the feasibility of suspending the source coil. Gimballing (pointing the axis of the source coil) was demonstrated over a limited range. With further development of the rotation sensing system, enhanced angular freedom should be possible

Spectrum of shoulder injuries in the baseball pitcher

Energy Technology Data Exchange (ETDEWEB)

Ouellette, Hugue; Bredella, Miriam; Palmer, William E.; Sheah, Kenneth; Torriani, Martin [Massachusetts General Hospital, Boston, Massachusetts (United States); Labis, John [Methodist Hospital, Houston, Texas (United States)

2008-06-15

This review describes a range of shoulder injuries experienced by baseball pitchers. It is estimated that more than 57% of pitchers suffer some form of shoulder injury during a playing season. Knowledge of the overhead throwing cycle is crucial for our understanding of these shoulder injuries. Baseball pitchers are prone to rotator cuff tears from tensile overload and impingement. Glenoid labrum degeneration or tears are also common, due to overuse syndrome (micro-instability), internal impingement and microtrauma. An understanding of the lesions involved in overhead throwing is crucial in baseball pitchers, as long-term disability can result from these injuries, sometimes with severe financial consequences to the player. (orig.)

Spectrum of shoulder injuries in the baseball pitcher

International Nuclear Information System (INIS)

Ouellette, Hugue; Bredella, Miriam; Palmer, William E.; Sheah, Kenneth; Torriani, Martin; Labis, John

2008-01-01

This review describes a range of shoulder injuries experienced by baseball pitchers. It is estimated that more than 57% of pitchers suffer some form of shoulder injury during a playing season. Knowledge of the overhead throwing cycle is crucial for our understanding of these shoulder injuries. Baseball pitchers are prone to rotator cuff tears from tensile overload and impingement. Glenoid labrum degeneration or tears are also common, due to overuse syndrome (micro-instability), internal impingement and microtrauma. An understanding of the lesions involved in overhead throwing is crucial in baseball pitchers, as long-term disability can result from these injuries, sometimes with severe financial consequences to the player. (orig.)

Forced two phase helium cooling of large superconducting magnets

International Nuclear Information System (INIS)

Green, M.A.; Burns, W.A.; Taylor, J.D.

1979-08-01

A major problem shared by all large superconducting magnets is the cryogenic cooling system. Most large magnets are cooled by some variation of the helium bath. Helium bath cooling becomes more and more troublesome as the size of the magnet grows and as geometric constraints come into play. An alternative approach to cooling large magnet systems is the forced flow, two phase helium system. The advantages of two phase cooling in many magnet systems are shown. The design of a two phase helium system, with its control dewar, is presented. The paper discusses pressure drop of a two phase system, stability of a two phase system and the method of cool down of a two phase system. The results of experimental measurements at LBL are discussed. Included are the results of cool down and operation of superconducting solenoids

The prevention of baseball and softball injuries.

Science.gov (United States)

Janda, David H

2003-04-01

Forty million individuals participate in organized softball leagues each year in the United States. Eighteen million additional student athletes and young adults also participate in organized baseball league play. In addition to being two of the most popular team sports in the United States, they also are responsible for a significant percentage of sports-related injuries that are sustained in the United States. Fortunately, numerous interventions independently have been shown to be effective at reducing the injury scenario, which has grown to be of epidemic proportion. Interventions such as break-away bases, batting helmets, face shields on helmets, lighter mass baseballs, and teaching and reiteration of the fundamentals of softball and baseball all have been effective in preventing millions of injuries and billions of dollars in healthcare costs each year in the United States.

Study on Impact Loading and Humerus Injury for Baseball

Science.gov (United States)

Sakai, Shinobu; Oda, Juhachi; Yonemura, Shigeru; Sakamoto, Jiro

In the United States and Japan, baseball is a very popular sport played by many people. However, the ball used is hard and moves fast. A professional baseball pitcher in good form can throw a ball at speeds upwards of 41.7m/s (150km/hr). If a ball at this speed hits the batter, serious injury can occur. In this paper we will describe our investigations on the impact of a baseball with living tissues by finite element analysis. Baseballs were projected at a load cell plate using a specialized pitching machine. The dynamic properties of the baseball were determined by comparing the wall-ball collision experimentally measuring the time history of the force and the displacement using dynamic finite element analysis software (ANSYS/ LS-DYNA). The finite element model representing a human humerus and its surrounding tissue was simulated for balls pitched at variable speeds and pitch types (knuckle and fastball). In so doing, the stress distribution and stress wave in the bone and soft tissue were obtained. From the results, the peak stress of the bone nearly yielded to the stress caused by a high fast ball. If the collision position or direction is moved from the center of the upper arm, it is assumed that the stress exuded on the humerus will be reduced. Some methods to reduce the severity of the injury which can be applied in actual baseball games are also discussed.

Large impedances and Majorana bound states in superconducting circuits

International Nuclear Information System (INIS)

Ulrich, Jascha

2017-01-01

Superconducting circuits offer the opportunity to study quantum mechanics on mesoscopic scales unimpeded by dissipation. This fact and the nonlinearity of the Josephson inductance make it possible to use superconducting circuits as artificial atoms whose long-lived states can be selectively addressed and studied. A pronounced nonlinearity of the energy spectrum, however, requires quantum fluctuations of the flux across the Josephson junction which are large on the scale of the superconducting flux quantum Φ Q =h/2e. This implies charge fluctuations below the single Cooper-pair limit via flux-charge duality. The localization of charge leads to a strong susceptibility to interactions with charges in the environment which has motivated the search for schemes to decouple charges from their environment. This thesis is concerned with theoretical challenges arising from two complementary approaches to this problem: the realization of large impedances and the fractionalization of electrons by means of Majorana bound states. In recent years, the decoupling of charges from the environment through reactive large impedances, so-called ''superinductances'' L, has attracted much interest. These inductances feature small parasitic capacitance C such that the characteristic impedance √(L/C) is much larger than the superconducting resistance quantum R Q =h/4e 2 . Superinductances have various applications ranging from qubit designs such as the 0-π qubit or the fluxonium to impedance matching, Bloch oscillations and the stabilization of phase slips in superconducting nanowires. Although there exists a well-established formalism for the quantization of superconducting circuits in terms of node fluxes, this formalism is ill-suited for the description of fast flux transport with localized charges in large-impedance environments. In particular, the nonlinear capacitive behavior of phase slip junctions cannot be modeled in a straightforward way using node fluxes

Corked bats, juiced balls, and humidors: The physics of cheating in baseball

Science.gov (United States)

Nathan, Alan M.; Smith, Lloyd V.; Faber, Warren L.; Russell, Daniel A.

2011-06-01

Three questions of relevance to Major League Baseball are investigated from a physics perspective. Can a baseball be hit farther with a corked bat? Is there evidence that the baseball is more lively today than in earlier years? Can storing baseballs in a temperature- or humidity-controlled environment significantly affect home run production? These questions are subjected to a physics analysis, including an experiment and an interpretation of the data. The answers to the three questions are no, no, and yes, respectively.

Superconducting materials for large scale applications

International Nuclear Information System (INIS)

Scanlan, Ronald M.; Malozemoff, Alexis P.; Larbalestier, David C.

2004-01-01

Significant improvements in the properties of superconducting materials have occurred recently. These improvements are being incorporated into the latest generation of wires, cables, and tapes that are being used in a broad range of prototype devices. These devices include new, high field accelerator and NMR magnets, magnets for fusion power experiments, motors, generators, and power transmission lines. These prototype magnets are joining a wide array of existing applications that utilize the unique capabilities of superconducting magnets:accelerators such as the Large Hadron Collider, fusion experiments such as ITER, 930 MHz NMR, and 4 Tesla MRI. In addition, promising new materials such as MgB2 have been discovered and are being studied in order to assess their potential for new applications. In this paper, we will review the key developments that are leading to these new applications for superconducting materials. In some cases, the key factor is improved understanding or development of materials with significantly improved properties. An example of the former is the development of Nb3Sn for use in high field magnets for accelerators. In other cases, the development is being driven by the application. The aggressive effort to develop HTS tapes is being driven primarily by the need for materials that can operate at temperatures of 50 K and higher. The implications of these two drivers for further developments will be discussed. Finally, we will discuss the areas where further improvements are needed in order for new applications to be realized

Shoulder injuries in US high school baseball and softball athletes, 2005-2008.

Science.gov (United States)

Krajnik, Stephanie; Fogarty, Kieran J; Yard, Ellen E; Comstock, R Dawn

2010-03-01

The objective of this study was to determine factors that are involved in shoulder injury rates among high school athletes who participate in organized baseball and softball. Baseball- and softball-related injury data were collected during the 2005-2008 academic years from approximately 74 nationally representative high schools via High School Reporting Information Online. Certified athletic trainers reported 91 baseball shoulder injuries and 40 softball shoulder injuries during 528147 and 399522 athlete exposures, respectively. The injury rate was 1.72 injuries per 10000 athlete exposures for baseball and 1.00 injuries per 10000 athlete exposures for softball. Muscle strain/incomplete tears were the most common injuries in both baseball (30.8%) and softball (35.0%). In practices, throwing, not including pitching, caused more than half of softball injuries (68.2%) as compared with competition injuries (23.5%; injury proportion ratio [IPR]: 2.90 [95% confidence interval (CI): 1.17-7.15]; P = .015), whereas pitching was the most common mechanism in causing shoulder injuries during baseball practice (41.9%) compared with competitions (25.6%; IPR: 1.64 [95% CI: 0.88-3.04]; P = .17). Eighty-one percent of the baseball shoulder injuries and 82.5% of the softball shoulder injuries were new. Ten percent of baseball athletes and 5.3% of softball athletes sustained injuries that required surgery (IPR: 1.40 [95% CI: 0.32-6.10]; P = .93). Injuries that were sustained while the athlete was on the pitcher's mound were significantly more likely to result in surgery than any other field position (IPR: 2.64 [95% CI: 1.65-4.21]; P = .0061). Injured baseball players were more than twice as likely to be pitchers. Although rates and patterns of shoulder injuries are similar between baseball and softball players, injury rates and patterns differ between field positions within each sport, as well as by injury severity and the athletes' year in school.

Incidence of injuries in high school softball and baseball players.

Science.gov (United States)

Shanley, Ellen; Rauh, Mitchell J; Michener, Lori A; Ellenbecker, Todd S

2011-01-01

Participation in high school sports has grown 16.1% over the last decade, but few studies have compared the overall injury risks in girls' softball and boys' baseball. To examine the incidence of injury in high school softball and baseball players. Cohort study. Greenville, South Carolina, high schools. Softball and baseball players (n = 247) from 11 high schools. Injury rates, locations, types; initial or subsequent injury; practice or game setting; positions played; seasonal trends. The overall incidence injury rate was 4.5/1000 athlete-exposures (AEs), with more injuries overall in softball players (5.6/1000 AEs) than in baseball players (4.0/1000 AEs). Baseball players had a higher initial injury rate (75.9/1000 AEs) than softball players (66.4/1000 AEs): rate ratio (RR) = 0.88, 95% confidence interval (CI) = 0.4, 1.7. The initial injury rate was higher than the subsequent injury rate for the overall sample (P softball (P Softball players were more likely to be injured in a game than were baseball players (RR = 1.92, 95% CI = 0.8, 4.3). Most injuries (77%) were mild (3.5/1000 AEs). The upper extremity accounted for the highest proportion of injuries (63.3%). The incidence of injury for pitchers was 37.3% and for position players was 15.3%. The rate of injury was highest during the first month of the season (7.96/1000 AEs). The incidence of injury was low for both softball and baseball. Most injuries were minor and affected the upper extremity. The injury rates were highest in the first month of the season, so prevention strategies should be focused on minimizing injuries and monitoring players early in the season.

Development of large bore superconducting magnet for wastewater treatment application

Energy Technology Data Exchange (ETDEWEB)

Liu, Hui Ming; Xu, Dong; Shen, Fuzhi; Zhang, Hengcheng; Li, Lafeng [State Key Laboratory of Technologies in Space Cryogenic Propellants, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing (China)

2017-03-15

Water issue, especially water pollution, is a serious issue of 21st century. Being an significant technique for securing water resources, superconducting magnetic separation wastewater system was indispensable. A large bore conduction-cooled magnet was custom-tailored for wastewater treatment. The superconducting magnet has been designed, fabricated and tested. The superconducting magnet was composed of NbTi solenoid coils with an effective horizontal warm bore of 400 mm and a maximum central field of 2.56T. The superconducting magnet system was cooled by a two-stage 1.5W 4K GM cryocooler. The NbTi solenoid coils were wound around an aluminum former that is thermally connected to the second stage cold head of the cryocooler through a conductive copper link. The temperature distribution along the conductive link was measured during the cool-down process as well as at steady state. The magnet was cooled down to 4.8K in approximately 65 hours. The test of the magnetic field and quench analysis has been performed to verify the safe operation for the magnet system. Experimental results show that the superconducting magnet reached the designed magnetic performance.

Structure design of the Westinghouse superconducting magnet for the Large Coil Program

International Nuclear Information System (INIS)

Domeisen, F.N.; Hackworth, D.T.; Stuebinger, L.R.

1978-01-01

In the on-going development of superconducting toroidal field coils for tokamak reactors, the Large Coil Program (LCP) managed by Union Carbide Corporation will include the design, fabrication, and testing of large superconducting coils to determine their feasibility for use in the magnetic fusion energy effort. Structural analysis of the large coil is essential to ensure adequate safety in the test coil design and confidence in the scalability of the design. This paper will discuss the action of tensile and shear loads on the various materials used in the coil. These loads are of magnetic and thermal origin

Analysis of Higher Order Modes in Large Superconducting Radio Frequency Accelerating Structures

CERN Document Server

Galek, Tomasz; Brackebusch, Korinna; Van Rienen, Ursula

2015-01-01

Superconducting radio frequency cavities used for accelerating charged particle beams are commonly used in accelerator facilities around the world. The design and optimization of modern superconducting RF cavities requires intensive numerical simulations. Vast number of operational parameters must be calculated to ensure appropriate functioning of the accelerating structures. In this study, we primarily focus on estimation and behavior of higher order modes in superconducting RF cavities connected in chains. To calculate large RF models the state-space concatenation scheme, an efficient hybrid method, is employed.

Stability and disturbance of large dc superconducting magnets

International Nuclear Information System (INIS)

Wang, S.T.

1981-01-01

This paper addresses the stability aspects of several successful dc superconducting magnets such as large bubble chamber magnets, and magnets for the Mirror Fusion Test Facility and MHD Research Facility. Specifically, it will cover Argonne National Laboratory 12-Foot Bubble Chamber magnets, the 15-foot Bubble Chamber magnets at Fermi National Laboratory, the MFTF-B Magnet System at Lawrence Livermore National Laboratory, the U-25B Bypass MHD Magnet, and the CFFF Superconducting MHD magnet built by Argonne National Laboratory. All of these magnets are cooled in pool-boiling mode. Magnet design is briefly reviewed. Discussed in detail are the adopted stability critera, analyses of stability and disturbance, stability simulation, and the final results of magnet performance and the observed coil disturbances

Medical management of youth baseball and softball tournaments.

Science.gov (United States)

Kanaan, Matthew; Ray, Tracy R

2013-01-01

The medical management of youth baseball and softball tournaments requires both proper planning and a basic awareness of commonly seen sport-specific injuries. While youth sporting events are designed to be a fun experience for all, injuries and emergencies will occur. With proper planning, and supplies, the impact of these issues can be minimized. This article will outline some basic principles for the medical personnel that may be involved in youth baseball and softball events.

Maxillofacial fractures sustained during baseball and softball.

Science.gov (United States)

Yamamoto, Kazuhiko; Murakami, Kazuhiro; Sugiura, Tsutomu; Ishida, Jun-ichi; Imai, Yuichiro; Fujimoto, Masaki; Kirita, Tadaaki

2009-04-01

The purpose of this study was to investigate the demographics, the type of impact, the site and the treatment of maxillofacial fractures sustained during baseball and softball to develop an effective preventive strategy. Data of 82 patients treated for baseball- and softball-related maxillofacial fractures at the Department of Oral and Maxillofacial Surgery, Nara Medical University between 1982 and 2007 were retrospectively analyzed. Injuries were found in 64 men in baseball and 16 men and two women in softball with average ages of 19.6 and 30.0 years, respectively. Fractures were caused by being hit by the ball in 61 patients followed by collision in 16 patients. Fractures of the mandible and the mid-face were found in 44 and 38 patients, respectively. The mental and angle region of the mandible and zygoma and alveolar bone of the maxilla were frequently involved. Treatment was mostly conservative. Open reduction and internal fixation were performed only in 15 patients. Most maxillofacial fractures in these sports were ball-related. Therefore, effective preventive means should be considered to protect against such injuries.

Advances in elementary particle physics with applied superconductivity. Contribution of superconducting technology to CERN large hadron collider accelerator

International Nuclear Information System (INIS)

Yamamoto, Akira

2011-01-01

The construction of the Large Hadron Collider (LHC) was started in 1994 and completed in 2008. The LHC consists of more than seven thousand superconducting magnets and cavities, which play an essential role in elementary particle physics and its energy frontier. Since 2010, physics experiments at the new energy frontier have been carried out to investigate the history and elementary particle phenomena in the early universe. The superconducting technology applied in the energy frontier physics experiments is briefly introduced. (author)

Lower thoracic rib stress fractures in baseball pitchers.

Science.gov (United States)

Gerrie, Brayden J; Harris, Joshua D; Lintner, David M; McCulloch, Patrick C

2016-01-01

Stress fractures of the first rib on the dominant throwing side are well-described in baseball pitchers; however, lower thoracic rib fractures are not commonly recognized. While common in other sports such as rowing, there is scant literature on these injuries in baseball. Intercostal muscle strains are commonly diagnosed in baseball pitchers and have a nearly identical presentation but also a highly variable healing time. The diagnosis of a rib stress fracture can predict a more protracted recovery. This case series presents two collegiate baseball pitchers on one team during the same season who were originally diagnosed with intercostal muscle strains, which following magnetic resonance imaging (MRI) were found to have actually sustained lower thoracic rib stress fractures. The first sustained a stress fracture of the posterior aspect of the right 8th rib on the dominant arm side, while the second presented with a left-sided 10th rib stress fracture on the nondominant arm side. In both cases, MRI was used to visualize the fractures as plain radiographs are insensitive and commonly negative early in patient presentation. Patients were treated with activity modification, and symptomatic management for 4-6 weeks with a graduated return to throwing and competition by 8-10 weeks. The repetitive high stresses incurred by pitching may cause either dominant or nondominant rib stress fractures and this should be included in the differential diagnosis of thoracic injuries in throwers. It is especially important that athletic trainers and team physicians consider this diagnosis, as rib fractures may have a protracted course and delayed return to play. Additionally, using the appropriate imaging techniques to establish an accurate diagnosis can help inform return-to-play decisions, which have important practical applications in baseball, such as roster management and eligibility.

Programs on large scale applications of superconductivity in Japan

International Nuclear Information System (INIS)

Yasukochi, K.; Ogasawara, T.

1974-01-01

History of the large scale application of superconductivity in Japan is reported. Experimental works on superconducting magnet systems for high energy physics have just begun. The programs are described by dividing into five categories: 1) MHD power generation systems, 2) superconducting rotating machines, 3) cryogenic power transmission systems, 4) magnetically levitated transportation, and 5) application to high energy physics experiments. The development of a big superconducting magnet for a 1,000 kW class generator was set up as a target of first seven year plan, which came to end in 1972, and continues for three years with the budget of 900 million yen from 1973 on. In the second phase plan, a prototype MHD generator is argued. A plan is contemplated to develop a synchronous generator with inner rotating field by Fuji Electric Co. The total budget for the future plans of superconducting power transmission system amounts to 20 billion yen for the first period of 8 approximately 9 years. In JNR's research and development efforts, several characteristic points are picked up: 1) linear motor drive with active side on ground, 2) loop track, 3) combined test run of maglev and LSM. The field test at the speed of 500 km/hr on a 7 km track is scheduled to be performed in 1975. The target of operation is in 1985. A 12 GeV proton synchrotron is now under construction for the study on high energy physics. Three ring intersecting storage accelerator is discussed for future plan. (Iwakiri, K.)

Preventive Effects of Eccentric Training on Acute Hamstring Muscle Injury in Professional Baseball

Science.gov (United States)

Seagrave, Richard A.; Perez, Luis; McQueeney, Sean; Toby, E. Bruce; Key, Vincent; Nelson, Joshua D.

2014-01-01

missed due to a hamstring injury during the 2012 season. This number was less than the 2011 season (273 days missed) and the 2010 season (309 days missed). Conclusion: Study results indicate the initiation of Nordic hamstring exercises may decrease the incidence of acute hamstring injuries and potentially decrease the total number of days missed due to injury in professional baseball players. Clinical Relevance: The financial and competitive interest in professional baseball players is of large importance to the player, team, and fans. Prevention of injuries is as important to all parties involved as the treatment and rehabilitation following an injury. This prospective study shows the initiation of a simple, free exercise can reduce the incidence of hamstring injury in the professional-level baseball player. PMID:26535336

Expert Baseball Batters Have Greater Sensitivity in Making Swing Decisions

Science.gov (United States)

Gray, Rob

2010-01-01

This study used signal detection theory to conceptualize the problem a baseball batter faces when deciding whether or not to swing at a pitch. It examined the launch angle (LA) criteria used by expert (college players) and less experienced (recreational league players) batters using a baseball batting simulation. This study showed that, although…

Safety Tips: Baseball (For Parents)

Science.gov (United States)

... and base runners and fielders frequently collide while running at top speed. Gear Guidelines As with all sports, wearing and using the right gear can go a long way toward preventing injuries. The amount of equipment required for baseball isn' ...

Superconductive technologies for the Large Hadron collider at CERN

CERN Document Server

Rossi, L

2000-01-01

The Large Hadron Collider (LHC) project is the largest plant based on superconductivity and cryogenics: 27 km of tunnel filled with superconducting magnets and other equipment that will be kept at 1.9 K. The dipole magnets have to generate a minimum magnetic field of 8.3 T to allow collisions of proton beams at an energy of 14 TeV in the centre of mass. The construction of LHC started in 1997 at CERN in Geneva and required 10 years of research and development on fine- filament NbTi superconducting wires and cables, on magnet technology and on He-II refrigerators. In particular the project needs the production of about 1000 tons of high-homogeneity NbTi with current densities of more than 2000 A mm/sup -2/ at 9 T and 1.9 K, with tight control also of all other cable properties such as magnetization, interstrand resistance and copper resistivity. The paper describes the main dipole magnets and reviews the most significant steps in the research and development, focusing on the issues related to the conductor, to...

Point contact tunneling spectroscopy apparatus for large scale mapping of surface superconducting properties

Energy Technology Data Exchange (ETDEWEB)

Groll, Nickolas; Pellin, Michael J. [Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439 (United States); Zasadzinksi, John F. [Illinois Institute of Technology, Chicago, Illinois 60616 (United States); Proslier, Thomas, E-mail: prolier@anl.gov [Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439 (United States); High Energy Physics Division, Argonne National Laboratory, Lemont, Illinois 60439 (United States)

2015-09-15

We describe the design and testing of a point contact tunneling spectroscopy device that can measure material surface superconducting properties (i.e., the superconducting gap Δ and the critical temperature T{sub C}) and density of states over large surface areas with size up to mm{sup 2}. The tip lateral (X,Y) motion, mounted on a (X,Y,Z) piezo-stage, was calibrated on a patterned substrate consisting of Nb lines sputtered on a gold film using both normal (Al) and superconducting (PbSn) tips at 1.5 K. The tip vertical (Z) motion control enables some adjustment of the tip-sample junction resistance that can be measured over 7 orders of magnitudes from a quasi-ohmic regime (few hundred Ω) to the tunnel regime (from tens of kΩ up to few GΩ). The low noise electronic and LabVIEW program interface are also presented. The point contact regime and the large-scale motion capabilities are of particular interest for mapping and testing the superconducting properties of macroscopic scale superconductor-based devices.

Structural materials for large superconducting magnets for tokamaks

International Nuclear Information System (INIS)

Long, C.J.

1976-12-01

The selection of structural materials for large superconducting magnets for tokamak-type fusion reactors is considered. The important criteria are working stress, radiation resistance, electromagnetic interaction, and general feasibility. The most advantageous materials appear to be face-centered-cubic alloys in the Fe-Ni-Cr system, but high-modulus composites may be necessary where severe pulsed magnetic fields are present. Special-purpose structural materials are considered briefly

The immediate effect of lumbar spine patterns of neuromuscular joint facilitation in young amateur baseball players.

Science.gov (United States)

Huo, Ming; Maruyama, Hitoshi; Kaneko, Takasumi; Naito, Daiki; Koiso, Yuta

2013-12-01

[Purpose] The aim of the study was to investigate the changes in baseball pitching velocity, the functional reach test (FR) and the simple reaction times (SRT) in young amateur baseball players after lumbar spine patterns of neuromuscular joint facilitation (NJF) treatment. [Subjects] The subjects were 11 young amateur baseball players. An NJF intervention and a proprioceptive neuromuscular facilitation (PNF) intervention were performed. The interventions were performed one after the other with one week between them. The order of the interventions was completely randomized. [Methods] The baseball pitching velocity, the FR and the SRT were evaluated before and after treatment. [Results] In the NJF group, there were significant differences in baseball pitching velocity, FR and SRT after treatment. In the PNF group, there was a significant difference in SRT after treatment. [Conclusion] NJF intervention shortens the SRT, increases the baseball pitching velocity and FR, and may be recommended to improve performance in baseball players.

Thermal properties of a large-bore cryocooled 10 T superconducting magnet for a hybrid magnet

International Nuclear Information System (INIS)

Ishizuka, M.; Hamajima, T.; Itou, T.; Sakuraba, J.; Nishijima, G.; Awaji, S.; Watanabe, K.

2010-01-01

A cryocooled 10 T superconducting magnet with a 360 mm room temperature bore has been developed for a hybrid magnet. The superconducting magnet cooled by four Gifford-McMahon cryocoolers has been designed to generate a magnetic field of 10 T. Since superconducting wires composed of coils were subjected to large hoop stress over 150 MPa and Nb 3 Sn superconducting wires particularly showed a low mechanical strength due to those brittle property, Nb 3 Sn wires strengthened by NbTi-filaments were developed for the cryocooled superconducting magnet. We have already reported that the hybrid magnet could generate the resultant magnetic field of 27.5 T by adding 8.5 T from the superconducting magnet and 19 T from a water-cooled Bitter resistive magnet, after the water-cooled resistive magnet was inserted into the 360 mm room temperature bore of the cryocooled superconducting magnet. When the hybrid magnet generated the field of 27.5 T, it achieved the high magnetic-force field (B x ∂Bz/∂z) of 4500 T 2 /m, which was useful for magneto-science in high fields such as materials levitation research. In this paper, we particularly focus on the cause that the cryocooled superconducting magnet was limited to generate the designed magnetic field of 10 T in the hybrid magnet operation. As a result, it was found that there existed mainly two causes as the limitation of the magnetic field generation. One was a decrease of thermal conductive passes due to exfoliation from the coil bobbin of the cooling flange. The other was large AC loss due to both a thick Nb 3 Sn layer and its large diameter formed on Nb-barrier component in Nb 3 Sn wires.

Shoulder range of motion measures as risk factors for shoulder and elbow injuries in high school softball and baseball players.

Science.gov (United States)

Shanley, Ellen; Rauh, Mitchell J; Michener, Lori A; Ellenbecker, Todd S; Garrison, J Craig; Thigpen, Charles A

2011-09-01

Range of motion deficits in shoulder external rotation (ER), internal rotation (IR), total rotation range of motion (ER + IR), and horizontal adduction (HA) have been retrospectively associated with overhand athletes' arm injuries. The authors expected the incidence of upper extremity injury in high school softball and baseball players with side-to-side shoulder range of motion deficits to be greater than the incidence of upper extremity injury in players with normal shoulder range of motion. Cohort study (prognosis); Level of evidence, 2. High school softball and baseball players (N = 246) participated. Before the start of the season, passive shoulder ER, IR, and HA were assessed at 90° of abduction with the scapula stabilized. Relative risk (RR) was calculated to examine range of motion measure, by categorical criteria, and risk of upper extremity injury. Twenty-seven shoulder and elbow injuries (9 softball, 18 baseball) were observed during the season. The dominant shoulder of all injured players and baseball players displayed a significant decrease in HA (P = .05) and IR (P = .04). The dominant shoulder total rotation of injured baseball players displayed a significant decrease (mean difference = 8.0° ± 0.1°; P = .05) as compared with the dominant shoulder of uninjured baseball players. Players who displayed a decrease of ≥25° of IR in the dominant shoulder were at 4 times greater risk of upper extremity injury compared with players with a .05). There are large mean deficits in shoulder IR and HA between injured and noninjured players, but not in ER or total rotation. Passive shoulder IR loss ≥25° as compared bilaterally was predictive of arm injury. Shoulder range of motion deficits differed between sports and appeared more predictive of injury for baseball players.

The neurosurgeon as baseball fan and inventor: Walter Dandy and the batter's helmet.

Science.gov (United States)

Brewster, Ryan; Bi, Wenya Linda; Smith, Timothy R; Gormley, William B; Dunn, Ian F; Laws, Edward R

2015-07-01

Baseball maintains one of the highest impact injury rates in all athletics. A principal causative factor is the "beanball," referring to a pitch thrown directly at a batter's head. Frequent morbidities elicited demand for the development of protective gear development in the 20th century. In this setting, Dr. Walter Dandy was commissioned to design a "protective cap" in 1941. His invention became widely adopted by professional baseball and inspired subsequent generations of batting helmets. As a baseball aficionado since his youth, Walter Dandy identified a natural partnership between baseball and medical practice for the reduction of beaning-related brain injuries. This history further supports the unique position of neurosurgeons to leverage clinical insights, inform innovation, and expand service to society.

Cryogenic techniques for large superconducting magnets in space

Science.gov (United States)

Green, M. A.

1989-01-01

A large superconducting magnet is proposed for use in a particle astrophysics experiment, ASTROMAG, which is to be mounted on the United States Space Station. This experiment will have a two-coil superconducting magnet with coils which are 1.3 to 1.7 meters in diameter. The two-coil magnet will have zero net magnetic dipole moment. The field 15 meters from the magnet will approach earth's field in low earth orbit. The issue of high Tc superconductor will be discussed in the paper. The reasons for using conventional niobium-titanium superconductor cooled with superfluid helium will be presented. Since the purpose of the magnet is to do particle astrophysics, the superconducting coils must be located close to the charged particle detectors. The trade off between the particle physics possible and the cryogenic insulation around the coils is discussed. As a result, the ASTROMAG magnet coils will be operated outside of the superfluid helium storage tank. The fountain effect pumping system which will be used to cool the coil is described in the report. Two methods for extending the operating life of the superfluid helium dewar are discussed. These include: operation with a third shield cooled to 90 K with a sterling cycle cryocooler, and a hybrid cryogenic system where there are three hydrogen-cooled shields and cryostat support heat intercept points.

Pitch Counts in Youth Baseball and Softball: A Historical Review.

Science.gov (United States)

Feeley, Brian T; Schisel, Jessica; Agel, Julie

2018-07-01

Pitching injuries are getting increased attention in the mass media. Many references are made to pitch counts and the role they play in injury prevention. The original purpose of regulating the pitch count in youth baseball was to reduce injury and fatigue to pitchers. This article reviews the history and development of the pitch count limit in baseball, the effect it has had on injury, and the evidence regarding injury rates on softball windmill pitching. Literature search through PubMed, mass media, and organizational Web sites through June 2015. Pitch count limits and rest recommendations were introduced in 1996 after a survey of 28 orthopedic surgeons and baseball coaches showed injuries to baseball pitchers' arms were believed to be from the number of pitches thrown. Follow-up research led to revised recommendations with more detailed guidelines in 2006. Since that time, data show a relationship between innings pitched and upper extremity injury, but pitch type has not clearly been shown to affect injury rates. Current surveys of coaches and players show that coaches, parents, and athletes often do not adhere to these guidelines. There are no pitch count guidelines currently available in softball. The increase in participation in youth baseball and softball with an emphasis on early sport specialization in youth sports activities suggests that there will continue to be a rise in injury rates to young throwers. The published pitch counts are likely to positively affect injury rates but must be adhered to by athletes, coaches, and parents.

A cooling concept for improved field winding performance in large superconducting ac generators

International Nuclear Information System (INIS)

Laskaris, T.E.

1977-01-01

An analytical study of a flow circuit for large superconducting generator rotors is presented. The flow circuit provides regulation of the level of liquid in the rotor externally by adjusting the helium supply pressure. It also protects the vapour cooled structural members of the rotor from overcooling during transient periods of operation. Furthermore, it is capable of reducing the winding temperature below 4.2 K thereby enhancing the superconductor's performance. For example, a large generator rotor with NbTi superconducting field winding experiences approximately a 50% increase in its critical current density compared to that at 4.2 K. (author)

Craniomaxillofacial fractures during recreational baseball and softball.

Science.gov (United States)

Bak, Matthew J; Doerr, Timothy D

2004-10-01

Baseball and softball are leading causes of sports-related facial trauma in the United States. We review our institutional experience (Strong Memorial Hospital, Rochester, NY) with these injuries and discuss measures to reduce their incidence. We review our institutions experience with facial fractures sustained during the course of a softball or baseball game over a 12-year period. A total of 38 patients were identified and medical records analyzed for patient demographics, type of impact, and fracture location. The male-to-female ratio was 3.2:1; mean age was 24.2 years, with 17 (45%) of the injuries occurring in the pediatric population. The majority of the injuries were caused by direct impact with the ball (68%), while player-player collisions (18%) and impact from a swung bat (13%) were responsible for the remaining injuries. There were a total of 39 fractures; 18 fractures (46%) involved the midface (level 2), skull (level 1) fractures accounted for 12 (31%), while 9 (23%) were mandibular (level 3) fractures. With 68% of the injuries resulting from a ball impact, we endorse the recommendations of the Consumer Product Safety Commission for the use of low-impact National Operating Committee on Standards for Athletic Equipment-approved baseballs and softballs for youth and recreational leagues.

Superconducting materials for large scale applications

Energy Technology Data Exchange (ETDEWEB)

Scanlan, Ronald M.; Malozemoff, Alexis P.; Larbalestier, David C.

2004-05-06

Significant improvements in the properties ofsuperconducting materials have occurred recently. These improvements arebeing incorporated into the latest generation of wires, cables, and tapesthat are being used in a broad range of prototype devices. These devicesinclude new, high field accelerator and NMR magnets, magnets for fusionpower experiments, motors, generators, and power transmission lines.These prototype magnets are joining a wide array of existing applicationsthat utilize the unique capabilities of superconducting magnets:accelerators such as the Large Hadron Collider, fusion experiments suchas ITER, 930 MHz NMR, and 4 Tesla MRI. In addition, promising newmaterials such as MgB2 have been discovered and are being studied inorder to assess their potential for new applications. In this paper, wewill review the key developments that are leading to these newapplications for superconducting materials. In some cases, the key factoris improved understanding or development of materials with significantlyimproved properties. An example of the former is the development of Nb3Snfor use in high field magnets for accelerators. In other cases, thedevelopment is being driven by the application. The aggressive effort todevelop HTS tapes is being driven primarily by the need for materialsthat can operate at temperatures of 50 K and higher. The implications ofthese two drivers for further developments will be discussed. Finally, wewill discuss the areas where further improvements are needed in order fornew applications to be realized.

Sensorimotor abilities predict on-field performance in professional baseball.

Science.gov (United States)

Burris, Kyle; Vittetoe, Kelly; Ramger, Benjamin; Suresh, Sunith; Tokdar, Surya T; Reiter, Jerome P; Appelbaum, L Gregory

2018-01-08

Baseball players must be able to see and react in an instant, yet it is hotly debated whether superior performance is associated with superior sensorimotor abilities. In this study, we compare sensorimotor abilities, measured through 8 psychomotor tasks comprising the Nike Sensory Station assessment battery, and game statistics in a sample of 252 professional baseball players to evaluate the links between sensorimotor skills and on-field performance. For this purpose, we develop a series of Bayesian hierarchical latent variable models enabling us to compare statistics across professional baseball leagues. Within this framework, we find that sensorimotor abilities are significant predictors of on-base percentage, walk rate and strikeout rate, accounting for age, position, and league. We find no such relationship for either slugging percentage or fielder-independent pitching. The pattern of results suggests performance contributions from both visual-sensory and visual-motor abilities and indicates that sensorimotor screenings may be useful for player scouting.

Oblique collisions of baseballs and softballs with a bat

Science.gov (United States)

Kensrud, Jeffrey R.; Nathan, Alan M.; Smith, Lloyd V.

2017-07-01

Experiments are done by colliding a swinging bat with a stationary baseball or softball. Each collision was recorded with high-speed cameras from which the post-impact speed, launch angle, and spin of the ball could be determined. Initial bat speeds were in the range 63-88 mph, producing launch angles in the range 0°-30° and spins in the range 0-3,500 rpm. The results are analyzed in the context of a ball-bat collision model, and the parameters of that model are determined. For both baseballs and softballs, the data are consistent with a mechanism whereby the ball grips the surface of the bat, stretching the ball in the transverse direction and resulting in a spin that was up to 40% greater than would be obtained by rolling contact of rigid bodies. Using a lumped parameter contact model, baseballs are shown to be less compliant tangentially than softballs. Implications of our results for batted balls in game situations are presented.

Large superconducting wind turbine generators

DEFF Research Database (Denmark)

Abrahamsen, Asger Bech; Magnusson, Niklas; Jensen, Bogi Bech

2012-01-01

and the rotation speed is lowered in order to limit the tip speed of the blades. The ability of superconducting materials to carry high current densities with very small losses might facilitate a new class of generators operating with an air gap flux density considerably higher than conventional generators...... and thereby having a smaller size and weight [1, 2]. A 5 MW superconducting wind turbine generator forms the basics for the feasibility considerations, particularly for the YBCO and MgB2 superconductors entering the commercial market. Initial results indicate that a 5 MW generator with an active weight of 34...

Development of large high current density superconducting solenoid magnets for use in high energy physics experiments

International Nuclear Information System (INIS)

Green, M.A.

1977-05-01

The development of a unique type of large superconducting solenoid magnet, characterized by very high current density windings and a two-phase helium tubular cooling system is described. The development of the magnet's conceptual design and the construction of two test solenoids are described. The successful test of the superconducting coil and its tubular cooling refrigeration system is presented. The safety, environmental and economic impacts of the test program on future developments in high energy physics are shown. Large solid angle particle detectors for colliding beam physics will analyze both charged and neutral particles. In many cases, these detectors will require neutral particles, such as gamma rays, to pass through the magnet coil with minimum interaction. The magnet coils must be as thin as possible. The use of superconducting windings allows one to minimize radiation thickness, while at the same time maximizing charged particle momentum resolution and saving substantial quantities of electrical energy. The results of the experimental measurements show that large high current density solenoid magnets can be made to operate at high stored energies. The superconducting magnet development described has a positive safety and environmental impact. The use of large high current density thin superconducting solenoids has been proposed in two high energy physics experiments to be conducted at the Stanford Linear Accelerator Center and Cornell University as a result of the successful experiments described

Superconducting electromagnets for large wind tunnel magnetic suspension and balance systems

International Nuclear Information System (INIS)

Boom, R.W.; Abdelsalam, M.K.; Bakerek, K.

1985-01-01

This paper presents a new design study of a Magnetic Suspension and Balance System (MSBS) for airplane models in a large 8 ft x 8 ft wind tunnel. New developments in the design include: use of a superconducting solenoid as a model core instead of magnetized iron; combination of permanent magnet material in the model wings along with four race-track coils to produce the required roll torque; and mounting of all the magnets in an integral cold structure instead of in separate cryostats. Design of superconducting solenoid model cores and practical experience with a small-scale prototype are discussed

Dominant-limb range-of-motion and humeral-retrotorsion adaptation in collegiate baseball and softball position players.

Science.gov (United States)

Hibberd, Elizabeth E; Oyama, Sakiko; Tatman, Justin; Myers, Joseph B

2014-01-01

Biomechanically, the motions used by baseball and softball pitchers differ greatly; however, the throwing motions of position players in both sports are strikingly similar. Although the adaptations to the dominant limb from overhead throwing have been well documented in baseball athletes, these adaptations have not been clearly identified in softball players. This information is important in order to develop and implement injury-prevention programs specific to decreasing the risk of upper extremity injury in softball athletes. To compare range-of-motion and humeral-retrotorsion characteristics of collegiate baseball and softball position players and of baseball and softball players to sex-matched controls. Cross-sectional study. Research laboratories and athletic training rooms at the University of North Carolina at Chapel Hill. Fifty-three collegiate baseball players, 35 collegiate softball players, 25 male controls (nonoverhead athletes), and 19 female controls (nonoverhead athletes). Range of motion and humeral retrotorsion were measured using a digital inclinometer and diagnostic ultrasound. Glenohumeral internal-rotation deficit, external-rotation gain, total glenohumeral range of motion, and humeral retrotorsion. Baseball players had greater glenohumeral internal-rotation deficit, total-range-of-motion, and humeral-retrotorsion difference than softball players and male controls. There were no differences between glenohumeral internal-rotation deficit, total-range-of-motion, and humeral-retrotorsion difference in softball players and female controls. Few differences were evident between softball players and female control participants, although range-of-motion and humeral-retrotorsion adaptations were significantly different than baseball players. The throwing motions are similar between softball and baseball, but the athletes adapt to the demands of the sport differently; thus, stretching/strengthening programs designed for baseball may not be the most

Cryogenic techniques for large superconducting magnets in space

International Nuclear Information System (INIS)

Green, M.A.

1988-12-01

A large superconducting magnet is proposed for use in a particle astrophysics experiment, ASTROMAG, which is to be mounted on the United States Space Station. This experiment will have a two-coil superconducting magnet with coils which are 1.3 to 1.7 meters in diameter. The two-coil magnet will have zero net magnetic dipole moment. The field 15 meters from the magnet will approach earth's field in low earth orbit. The issue of high Tc superconductor will be discussed in the paper. The reasons for using conventional niobium-titanium superconductor cooled with superfluid helium will be presented. Since the purpose of the magnet is to do particle astrophysics, the superconducting coils must be located close to the charged particle detectors. The trade off between the particle physics possible and the cryogenic insulation around the coils is discussed. As a result, the ASTROMAG magnet coils will be operated outside of the superfluid helium storage tank. The fountain effect pumping system which will be used to cool the coil is described in the report. Two methods for extending the operating life of the superfluid helium dewar are discussed. These include: operation with a third shield cooled to 90 K with a sterling cycle cryocooler, and a hybrid cryogenic system where there are three hydrogen-cooled shields and cryostat support heat intercept points. Both of these methods will extend the ASTROMAG cryogenic operating life from 2 years to almost 4 years. 14 refs., 8 figs., 4 tabs

Location, Location, Location: The Transmission of Racist Ideology in Baseball Cards

Science.gov (United States)

Regoli, Robert M.; Hewitt, John D.; Munoz, Robert, Jr.; Regoli, Adam M.

2004-01-01

While on the surface baseball cards may appear to be a mundane object of child's play, they are precious tools for examining U.S. society. Baseball cards not only hold a wealth of information regarding the players they feature they also reveal much about the state of society at the time of their production and the individuals who collect them. In…

Application of the matching law to pitch selection in professional baseball.

Science.gov (United States)

Cox, David J; Sosine, Jacob; Dallery, Jesse

2017-04-01

This study applied the generalized matching equation (GME) to pitch selection in professional baseball. The GME was fitted to the relation between pitch selection and hitter outcomes for five professional baseball pitchers during the 2014 Major League Baseball season. The GME described pitch selection well. Pitch allocation varied across different game contexts such as inning, count, and number of outs in a manner consistent with the GME. Finally, within games, bias decreased for four of the five pitchers and the sensitivity parameter increased for three of the five pitchers. The results extend the generality of the GME to multialternative natural sporting contexts, and demonstrate the influence of context on behavior in natural environments. © 2017 Society for the Experimental Analysis of Behavior.

Visual abilities distinguish pitchers from hitters in professional baseball.

Science.gov (United States)

Klemish, David; Ramger, Benjamin; Vittetoe, Kelly; Reiter, Jerome P; Tokdar, Surya T; Appelbaum, Lawrence Gregory

2018-01-01

This study aimed to evaluate the possibility that differences in sensorimotor abilities exist between hitters and pitchers in a large cohort of baseball players of varying levels of experience. Secondary data analysis was performed on 9 sensorimotor tasks comprising the Nike Sensory Station assessment battery. Bayesian hierarchical regression modelling was applied to test for differences between pitchers and hitters in data from 566 baseball players (112 high school, 85 college, 369 professional) collected at 20 testing centres. Explanatory variables including height, handedness, eye dominance, concussion history, and player position were modelled along with age curves using basis regression splines. Regression analyses revealed better performance for hitters relative to pitchers at the professional level in the visual clarity and depth perception tasks, but these differences did not exist at the high school or college levels. No significant differences were observed in the other 7 measures of sensorimotor capabilities included in the test battery, and no systematic biases were found between the testing centres. These findings, indicating that professional-level hitters have better visual acuity and depth perception than professional-level pitchers, affirm the notion that highly experienced athletes have differing perceptual skills. Findings are discussed in relation to deliberate practice theory.

Structural design of superconducting magnets for the large coil program

International Nuclear Information System (INIS)

Gray, W.H.; Long, C.J.; Stoddart, W.C.T.

1979-09-01

The Large Coil Program (LCP) is a research, development, and demonstration effort specifically for the advancement of the technologies involved in the production of large superconducting magnets. This paper presents a review of the status of the structural designs, analysis methods, and verification tests being performed by the participating LCP design teams in the USA, Switzerland, Japan, and the Federal Republic of Germany. The significant structural mechanics concerns that are being investigated with the LCP are presented

Superconductivity

CERN Document Server

Thomas, D B

1974-01-01

A short general review is presented of the progress made in applied superconductivity as a result of work performed in connection with the high-energy physics program in Europe. The phenomenon of superconductivity and properties of superconductors of Types I and II are outlined. The main body of the paper deals with the development of niobium-titanium superconducting magnets and of radio-frequency superconducting cavities and accelerating structures. Examples of applications in and for high-energy physics experiments are given, including the large superconducting magnet for the Big European Bubble Chamber, prototype synchrotron magnets for the Super Proton Synchrotron, superconducting d.c. beam line magnets, and superconducting RF cavities for use in various laboratories. (0 refs).

Superconducting (radiation hardened) magnets for mirror fusion devices

International Nuclear Information System (INIS)

Henning, C.D.; Dalder, E.N.C.; Miller, J.R.; Perkins, J.R.

1983-01-01

Superconducting magnets for mirror fusion have evolved considerably since the Baseball II magnet in 1970. Recently, the Mirror Fusion Test Facility (MFTF-B) yin-yang has been tested to a full field of 7.7 T with radial dimensions representative of a full scale reactor. Now the emphasis has turned to the manufacture of very high field solenoids (choke coils) that are placed between the tandem mirror central cell and the yin-yang anchor-plug set. For MFTF-B the choke coil field reaches 12 T, while in future devices like the MFTF-Upgrade, Fusion Power Demonstration and Mirror Advanced Reactor Study (MARS) reactor the fields are doubled. Besides developing high fields, the magnets must be radiation hardened. Otherwise, thick neutron shields increase the magnet size to an unacceptable weight and cost. Neutron fluences in superconducting magnets must be increased by an order of magnitude or more. Insulators must withstand 10 10 to 10 11 rads, while magnet stability must be retained after the copper has been exposed to fluence above 10 19 neutrons/cm 2

A New Facility for Testing Superconducting Solenoid Magnets with Large Fringe Fields at Fermilab

Energy Technology Data Exchange (ETDEWEB)

Orris, D. [Fermilab; Carcagno, R. [Fermilab; Nogiec, J. [Fermilab; Rabehl, R. [Fermilab; Sylvester, C. [Fermilab; Tartaglia, M. [Fermilab

2013-09-01

Testing superconducting solenoid with no iron flux return can be problematic for a magnet test facility due to the large magnetic fringe fields generated. These large external fields can interfere with the operation of equipment while precautions must be taken for personnel supporting the test. The magnetic forces between the solenoid under test and the external infrastructure must also be taken under consideration. A new test facility has been designed and built at Fermilab specifically for testing superconducting magnets with large external fringe fields. This paper discusses the test stand design, capabilities, and details of the instrumentation and controls with data from the first solenoid tested in this facility: the Muon Ionization Cooling Experiment (MICE) coupling coil.

Baseball and softball sliding injuries: incidence and correlates during one high school league varsity season.

Science.gov (United States)

Stovak, Mark; Parikh, Amit; Harvey, Anne T

2012-11-01

To estimate injury rates associated with sliding in high school baseball and softball. Prospective cohort study. Community high school athletic events. Ten high school varsity baseball and softball teams over 1 season. All sliding attempts were recorded during each game and recorded as headfirst, feetfirst, or diveback. Base type, playing surface, and field conditions were also noted. Injury exposure rates by game exposures and sliding/diveback exposures. Data were collected from 153 baseball games and 166 softball games. A greater proportion of slides were associated with injury in softball than in baseball (42.0 and 4.9 per 1000 slides; P softball (55 vs 35 per 1000 slides; P = 0.74). More powerful studies are required to determine whether efforts to prevent baseball sliding injuries at the high school level should focus on better education in sliding technique or changes in equipment. Softball players are vulnerable to injury when wearing inadequate protective sliding apparel.

Real Time Baseball Database

Science.gov (United States)

Fukue, Yasuhiro

The author describes the system outline, features and operations of "Nikkan Sports Realtime Basaball Database" which was developed and operated by Nikkan Sports Shimbun, K. K. The system enables to input numerical data of professional baseball games as they proceed simultaneously, and execute data updating at realtime, just-in-time. Other than serving as supporting tool for prepareing newspapers it is also available for broadcasting media, general users through NTT dial Q2 and others.

Piotron at SIN - a large superconducting double torus spectrometer

International Nuclear Information System (INIS)

Horvath, I.; Vecsey, G.; Zellweger, J.

1981-01-01

A test facility for radiation therapy with negative /pi/-mesons was constructed in Switzerland. The facility is a large double torus spectrometer similar to the Stanford design. For variation of stopping depth different momenta are selected by variation of the magnetic field. Superconducting ac magnets are necessary for tumor scanning and represent a major part of such a facility. Main design features and performance are reported. 10 refs

Technological stakes of LHC, the large superconducting collider in project at CERN

International Nuclear Information System (INIS)

Lebrun, P.

1991-01-01

The LHC large superconducting particle collider project is presented, with particular emphasis on its major technological requirements and returns, mostly in the domains of high-field electromagnets, superfluid helium cryogenics, and integration of such advanced techniques in a large machine. The corresponding cooperation and technological transfer to European laboratories and industries are briefly discussed [fr

Slip-Stick Mechanism in Training the Superconducting Magnets in the Large Hadron Collider

CERN Document Server

Granieri, P P; Todesco, E

2011-01-01

Superconducting magnets can exhibit training quenches during successive powering to reaching nominal performance. The slip–stick motion of the conductors is considered to be one of the mechanisms of training. In this paper, we present a simple quantitative model where the training is described as a discrete dynamical system matching the equilibrium between the energy margin of the superconducting cable and the frictional energy released during the conductor motion. The model can be explicitly solved in the linearized case, showing that the short sample limit is reached via a power law. Training phenomena have a large random component. A large set of data of the large hadron collider magnet tests is postprocessed according to previously defined methods to extract an average training curve for dipoles and quadrupoles. These curves show the asymptotic power law predicted by the model. The curves are then fit through the model, which has two free parameters. The model shows good agreement over a large range, bu...

Slip-Stick Mechanism in Training the Superconducting Magnets in the Large Hadron Collider

CERN Document Server

Granieri, P P; Lorin, C

2011-01-01

Superconducting magnets can exhibit training quenches during successive powering to reaching nominal performance. The slip-stick motion of the conductors is considered to be one of the mechanisms of training. In this paper, we present a simple quantitative model where the training is described as a discrete dynamical system matching the equilibrium between the energy margin of the superconducting cable and the frictional energy released during the conductor motion. The model can be explicitly solved in the linearized case, showing that the short sample limit is reached via a power law. Training phenomena have a large random component. A large set of data of the large hadron collider magnet tests is postprocessed according to previously defined methods to extract an average training curve for dipoles and quadrupoles. These curves show the asymptotic power law predicted by the model. The curves are then fit through the model, which has two free parameters. The model shows good agreement over a large range, but ...

Saved at Home: Christian Branding and Faith Nights in the "Church of Baseball"

Science.gov (United States)

Butterworth, Michael L.

2011-01-01

Baseball has enjoyed its status as the "national pastime" in part because it has been associated with democracy. To the extent that baseball, as an institution of civil religion, fosters pluralism and inclusion, it can indeed be viewed in democratic terms. In recent years, the advent of conservative Christian events called "Faith Nights" threatens…

Three computer codes for safety and stability of large superconducting magnets

International Nuclear Information System (INIS)

Turner, L.R.

1985-01-01

For analyzing the safety and stability of large superconducting magnets, three computer codes TASS, SHORTURN, and SSICC have been developed, applicable to bath-cooled magnets, bath-cooled magnets with shorted turns, and magnets with internally cooled conductors respectively. The TASS code is described, and the use of the three codes is reviewed

Rotation analysis on large complex superconducting cables based on numerical modeling and experiments

NARCIS (Netherlands)

Qin, Jinggang; Yue, Donghua; Zhang, Xingyi; Wu, Yu; Liu, Xiaochuan; Liu, Huajun; Jin, Huan; Dai, Chao; Nijhuis, Arend; Zhou, Chao; Devred, Arnaud

2018-01-01

The conductors used in large fusion reactors, e.g. ITER, CFETR and DEMO, are made of cable-in-conduit conductor (CICC) with large diameters up to about 50 mm. The superconducting and copper strands are cabled around a central spiral and then wrapped with stainless-steel tape of 0.1 mm thickness. The

Indirectly cooled large thin superconducting CDF solenoid

International Nuclear Information System (INIS)

Kondo, Kunitaka; Mori, Shigeki; Yoshizaki, Ryozo; Saito, Ryusei; Asano, Katsuhiko.

1985-01-01

The manufacturing technique of the indirectly cooled large thin superconducting solenoid for the collider detector facility (CDF solenoid) has been studied through cooperation of University of Tsukuba and the National Laboratory for High Energy Physics of the Ministry of Education of Japan, and the Fermi National Accelerator Laboratory in the U.S. Fabrication and testing of the solenoid has recently been completed by Hitachi. The CDF solenoid has a large-sized thin structure for meeting the requirement by experiments to be applied. Hitachi has thus developed a variety of new technologies including the design standard, coil cooling method, material selection, and manufacturing technique in accordance with experimental data, which were confirmed in a series of analyses and tests made on various prototypes. The CDF solenoid, built using Hitachi's new technologies, is of the world's top class among equipment of this type. This paper outlines the design criteria for the major components employed in the CDF solenoid and the test results of the solenoid. (author)

Scapula Kinematics of Youth Baseball Players

Directory of Open Access Journals (Sweden)

Oliver Gretchen

2015-12-01

Full Text Available Literature has revealed the importance of quantifying resting scapular posture in overhead athletes as well as quantifying scapular kinematics during dynamic movement. Prior to this project much of the attention in throwing research had been focused on the position of the humerus without description of the positioning of the scapula. Therefore, it was the purpose of this study to present scapular kinematics during pitching in youth baseball players. Twenty-five youth baseball players (age 11.3 + 1.0 years; body height 152.4 + 9.0 cm; body mass 47.5 + 11.3 kg, with no history of injury, participated in the study. Scapular kinematics at the events of maximum humeral external rotation (MER and maximum humeral internal rotation (MIR during the pitching motion were assessed three-dimensionally while pitching fastballs for strikes. Results revealed that at the event of MER, the scapula was in a position of retraction, upward rotation and a posterior tilt. While at the event of MIR, the scapula was protracted, upward rotated and tilted anteriorly.

Baseball fans don't like lumpy batters: Influence of domain knowledge on the access of subordinate meanings.

Science.gov (United States)

Wiley, Jennifer; George, Tim; Rayner, Keith

2016-11-08

Two experiments investigated the effects of domain knowledge on the resolution of ambiguous words with dominant meanings related to baseball. When placed in a sentence context that strongly biased toward the non-baseball meaning (positive evidence), or excluded the baseball meaning (negative evidence), baseball experts had more difficulty than non-experts resolving the ambiguity. Sentence contexts containing positive evidence supported earlier resolution than did the negative evidence condition for both experts and non-experts. These experiments extend prior findings, and can be seen as support for the reordered access model of lexical access, where both prior knowledge and discourse context influence the availability of word meanings.

A Cryogenic Test Stand for Large Superconducting Solenoid Magnets

Energy Technology Data Exchange (ETDEWEB)

Rabehl, R. [Fermilab; Carcagno, R. [Fermilab; Nogiec, J. [Fermilab; Orris, D. [Fermilab; Soyars, W. [Fermilab; Sylvester, C. [Fermilab

2013-01-01

A new test stand for testing large superconducting solenoid magnets at the Fermilab Central Helium Liquifier (CHL) has been designed, and operated. This test stand has been used to test a coupling coil for the Muon Ionization Cooling Experiment (MICE), and future uses include solenoids for the Fermilab mu2e experiment. This paper describes the test stand design and operation including controlled cool-down and warm-up. Overviews of the process controls system and the quench management system are also included.

Conceptual design report for a superconducting coil suitable for use in the large solenoid detector at the SSC [Superconducting Super Collider

International Nuclear Information System (INIS)

Fast, R.W.; Grimson, J.H.; Krebs, H.J.; Kephart, R.D.; Theriot, D.; Wands, R.H.

1989-01-01

The conceptual design of a large superconducting solenoid suitable for a magnetic detector at the Superconducting Super Collider (SSC) was done at Fermilab. The magnet will provide a magnetic field of 1.7 T over a volume 8 m in diameter by 16 m long. The particle-physics calorimetry will be inside the field volume and so the coil will be bath cooled and cryostable; the vessels will be stainless steel. Predictability of performance and the ability to safely negotiate all probable failure modes, including a quench, are important items of the design philosophy. Our conceptual design of the magnet and calorimeter has convinced us that this magnet is a reasonable extrapolation of present technology and is therefore feasible. The principal difficulties anticipated are those associated with the very large physical dimensions and stored energy of the magnet. 5 figs

Large superconducting coil fabrication development

International Nuclear Information System (INIS)

Brown, R.L.; Allred, E.L.; Anderson, W.C.; Burn, P.B.; Deaderick, R.I.; Henderson, G.M.; Marguerat, E.F.

1975-01-01

Toroidal fields for some fusion devices will be produced by an array of large superconducting coils. Their size, space limitation, and field requirements dictate that they be high performance coils. Once installed, accessibility for maintenance and repairs is severely restricted; therefore, good reliability is an obvious necessity. Sufficient coil fabrication will be undertaken to develop and test methods that are reliable, fast, and economical. Industrial participation will be encouraged from the outset to insure smooth transition from development phases to production phases. Initially, practice equipment for three meter bore circular coils will be developed. Oval shape coil forms will be included in the practice facility later. Equipment that is more automated will be developed with the expectation of winding faster and obtaining good coil quality. Alternate types of coil construction, methods of winding and insulating, will be investigated. Handling and assembly problems will be studied. All technology developed must be feasible for scaling up when much larger coils are needed. Experimental power reactors may need coils having six meter or larger bores

Skin conditions of baseball, cricket, and softball players.

Science.gov (United States)

Farhadian, Joshua A; Tlougan, Brook E; Adams, Brian B; Leventhal, Jonathan S; Sanchez, Miguel R

2013-07-01

Each year in the United States over 80 million people participate in bat-and-ball sports, for example baseball and softball. Cricket, the world's second most popular sport, is enjoyed by hundreds of millions of participants in such countries as India, Pakistan, Australia, New Zealand, Bangladesh, South Africa, West Indies, Sri Lanka, United Kingdom, and Zimbabwe. Although any player can develop skin disease as a result of participation in these bat-and-ball sports, competitive team athletes are especially prone to skin problems related to infection, trauma, allergy, solar exposure, and other causes. These diseases can produce symptoms that hinder individual athletic performance and participation. In this review, we discuss the diagnosis and best-practice management of skin diseases that can develop as a result of participation in baseball, softball, and cricket.

A comparison of static near stereo acuity in youth baseball/softball players and non-ball players.

Science.gov (United States)

Boden, Lauren M; Rosengren, Kenneth J; Martin, Daniel F; Boden, Scott D

2009-03-01

Although many aspects of vision have been investigated in professional baseball players, few studies have been performed in developing athletes. The issue of whether youth baseball players have superior stereopsis to nonplayers has not been addressed specifically. The purpose of this study was to determine if youth baseball/softball players have better stereo acuity than non-ball players. Informed consent was obtained from 51 baseball/softball players and 52 non-ball players (ages 10 to 18 years). Subjects completed a questionnaire, and their static near stereo acuity was measured using the Randot Stereotest (Stereo Optical Company, Chicago, Illinois). Stereo acuity was measured as the seconds of arc between the last pair of images correctly distinguished by the subject. The mean stereo acuity score was 25.5 +/- 1.7 seconds of arc in the baseball/softball players and 56.2 +/- 8.4 seconds of arc in the non-ball players. This difference was statistically significant (P softball players had significantly better static stereo acuity than non-ball players, comparable to professional ball players.

Early Sport Specialization: Effectiveness and Risk of Injury in Professional Baseball Players

OpenAIRE

Wilhelm, Andrew; Choi, Changryol; Deitch, John

2017-01-01

Background: The rate of early sport specialization in professional baseball players is unknown. Purpose: To report the incidence and age of sport specialization in current professional baseball players and the impact of early specialization on the frequency of serious injuries sustained during the players’ careers. We also queried participants about when serious injuries occurred, the players’ current position on the field, and their opinions regarding the need for young athletes to specializ...

Evaluation of safety balls and faceguards for prevention of injuries in youth baseball.

Science.gov (United States)

Marshall, Stephen W; Mueller, Frederick O; Kirby, Daniel P; Yang, Jingzhen

2003-02-05

Safety balls and faceguards are widely used in youth baseball, but their effectiveness in reducing injury is unknown. To evaluate the association of the use of faceguards and safety balls and injuries in youth baseball. Ecological study using a national database of compensated insurance claims maintained by Little League Baseball Incorporated, combined with data on the number of participants in Little League and data from a census of protective equipment usage for youth aged 5 to 18 years participating in Little League Baseball in the United States during 1997-1999. Rate of injury and injury rate ratio comparing users with nonusers of protective equipment. A total of 6 744 240 player-seasons of follow-up and 4233 compensated injury claims were available for analysis. The absolute incidence of compensated injury per 100 000 player-seasons was 28.02 (95% confidence interval [CI], 26.76-29.29) for ball-related injury and 2.71 (95% CI, 2.32-3.11) for facial injury. Overall, use of safety balls was associated with a reduced risk of ball-related injury (adjusted rate ratio, 0.77; 95% CI, 0.64-0.93). This reduction was essentially due to 1 type of safety ball, known as the reduced-impact ball (adjusted rate ratio, 0.72; 95% CI, 0.57-0.91). Use of faceguards reduced the risk of facial injury (adjusted rate ratio, 0.65; 95% CI, 0.43-0.98). Metal and plastic guards appeared to be equally effective. Safety balls appeared to be more effective in the minor division (ages 7-12 years) than in the regular division (ages 9-12 years). Reduced-impact balls and faceguards were associated with a reduced risk of injury in youth baseball. These findings support increased usage of these items; however, it should be noted that the absolute incidence of injury in youth baseball is low and that these equipment items do not prevent all injuries.

Skill-Specific Changes in Somatosensory Nogo Potentials in Baseball Players.

Directory of Open Access Journals (Sweden)

Koya Yamashiro

Full Text Available Athletic training is known to induce neuroplastic alterations in specific somatosensory circuits, which are reflected by changes in somatosensory evoked potentials and event-related potentials. The aim of this study was to clarify whether specific athletic training also affects somatosensory Nogo potentials related to the inhibition of movements. The Nogo potentials were recorded at nine cortical electrode positions (Fz, Cz, Pz, F3, F4, C3, C4, P3 and P4 in 12 baseball players (baseball group and in 12 athletes in sports, such as track and field events and swimming, that do not require response inhibition, such as batting for training or performance (sports group. The Nogo potentials and Go/Nogo reaction times (Go/Nogo RTs were measured under a somatosensory Go/Nogo paradigm in which subjects were instructed to rapidly push a button in response to stimulus presentation. The Nogo potentials were obtained by subtracting the Go trial from the Nogo trial. The peak Nogo-N2 was significantly shorter in the baseball group than that in the sports group. In addition, the amplitude of Nogo-N2 in the frontal area was significantly larger in the baseball group than that in the sports group. There was a significant positive correlation between the latency of Nogo-N2 and Go/Nogo RT. Moreover, there were significant correlations between the Go/Nogo RT and both the amplitude of Nogo-N2 and Nogo-P3 (i.e., amplitude of the Nogo-potentials increases with shorter RT. Specific athletic training regimens may induce neuroplastic alterations in sensorimotor inhibitory processes.

Cryogenic expansion joint for large superconducting magnet structures

Science.gov (United States)

Brown, Robert L.

1978-01-01

An expansion joint is provided that accommodates dimensional changes occurring during the cooldown and warm-up of large cryogenic devices such as superconducting magnet coils. Flattened tubes containing a refrigerant such as gaseous nitrogen (N.sub.2) are inserted into expansion spaces in the structure. The gaseous N.sub.2 is circulated under pressure and aids in the cooldown process while providing its primary function of accommodating differential thermal contraction and expansion in the structure. After lower temperatures are reached and the greater part of the contraction has occured, the N.sub.2 liquefies then solidifies to provide a completely rigid structure at the cryogenic operating temperatures of the device.

Thermal anchoring of wires in large scale superconducting coil test experiment

International Nuclear Information System (INIS)

Patel, Dipak; Sharma, A.N.; Prasad, Upendra; Khristi, Yohan; Varmora, Pankaj; Doshi, Kalpesh; Pradhan, S.

2013-01-01

Highlights: • We addressed how thermal anchoring in large scale coil test is different compare to small cryogenic apparatus? • We did precise estimation of thermal anchoring length at 77 K and 4.2 K heat sink in large scale superconducting coil test experiment. • We addressed, the quality of anchoring without covering entire wires using Kapton/Teflon tape. • We obtained excellent results in temperature measurement without using GE Varnish by doubling estimated anchoring length. -- Abstract: Effective and precise thermal anchoring of wires in cryogenic experiment is mandatory to measure temperature in milikelvin accuracy and to avoid unnecessary cooling power due to additional heat conduction from room temperature (RT) to operating temperature (OT) through potential, field, displacement and stress measurement instrumentation wires. Instrumentation wires used in large scale superconducting coil test experiments are different compare to cryogenic apparatus in terms of unique construction and overall diameter/area due to errorless measurement in large time-varying magnetic field compare to small cryogenic apparatus, often shielded wires are used. Hence, along with other variables, anchoring techniques and required thermal anchoring length are entirely different in this experiment compare to cryogenic apparatus. In present paper, estimation of thermal anchoring length of five different types of instrumentation wires used in coils test campaign at Institute for Plasma Research (IPR), India has been discussed and some temperature measurement results of coils test campaign have been presented

Vascular changes of the hand in professional baseball players with emphasis on digital ischemia in catchers.

Science.gov (United States)

Ginn, T Adam; Smith, Adam M; Snyder, Jon R; Koman, L Andrew; Smith, Beth P; Rushing, Julia

2005-07-01

Repetitive trauma to the hand is a concern for baseball players. The present study investigated the effects of repetitive trauma and the prevalence of microvascular pathological changes in the hands of minor league professional baseball players. In contrast to previous investigators, we documented the presence of abnormalities in younger, asymptomatic individuals. Thirty-six baseball players on active minor league rosters underwent a history and physical examination of both hands as well as additional specialized tests, including Doppler ultrasound, a timed Allen test, determination of digital brachial pressure indices, and ring sizing of fingers. Data were compared between gloved hands and throwing hands, hitters and nonhitters, and players at four different positions (catcher [nine subjects], outfielder [seven subjects], infielder [five subjects], and pitcher [fifteen subjects]). Digital brachial indices in the ring fingers of the gloved (p healthy professional baseball players in all positions, with a significantly higher prevalence in catchers, prior to the development of clinically important ischemia. Repetitive trauma resulting from the impact of the baseball also leads to digital hypertrophy in the index finger of the gloved hand of catchers. Gloves currently used by professional catchers do not adequately protect the hand from repetitive trauma.

Systematic Review of Traumatic Brain Injuries in Baseball and Softball: A Framework for Prevention.

Science.gov (United States)

Cusimano, Michael D; Zhu, Alice

2017-01-01

Traumatic brain injuries (TBIs) are an important public health challenge. The classification of baseball and softball as low contact sports and their association with extremity injuries cause individuals to overlook the risk of TBI in baseball and softball. To summarize our knowledge of the epidemiology and risk factors of TBIs associated with baseball and softball with an aim to better design and implement preventive strategies. A search algorithm containing keywords that were synonymous to the terms "TBI," "baseball" was applied to the following nine databases: MEDLINE, Scopus, PubMed, EMBASE, CINAHL, Healthstar, PsychINFO, AMED, Cochrane library. Cited reference lists of identified articles were also consulted yielding a total of eighty-eight articles for full review. The search was concluded on November 14, 2016. The level of evidence was evaluated according to the guidelines from Strengthening the Reporting of Observational Studies in Epidemiology statement. Twenty-nine articles published between 2000 and 2016 met the criteria for analysis. Collectively, they examined the years 1982-2015 and identified 242,731 baseball-and softball-related TBIs. The most explored outcome of TBI was concussion. The average injury rate per 1,000 athletic exposures was 0.13 (range 0.03-0.46). The most common mechanism of injury was being struck by bat for younger players and being struck by ball for older athletes (adolescent and beyond). Rates of TBI were on average 4.17 times greater in games compared to practices. Females were on average 2.04 times more likely to sustain a TBI than males. Severity of TBIs varied considerably from mild and returning to the field on the same day, to immediate death. Generally, there is poor compliance with helmet use and return-to-play post-concussion guidelines. An increase TBI rates was observed over time. Multifaceted preventive strategies must be implemented to reduce the frequency and burden of these injuries. It is difficult to compare the

Efficiency of application of special exercises and exercises with the use of baseball pitching machine

Directory of Open Access Journals (Sweden)

Agapov D.V.

2012-01-01

Full Text Available Efficiency of the approach on making up coordination capabilities and technical tactical performances in baseball is confirmed. 100 boys (age 12-14 years take part in experiment. Relative analysis of a level of development of coordination capabilities and technical tactical readiness of baseball players is carried out. The level of development of technical readiness after experiment under the program «pitch, hit and run» is taped. The frame of special exercises with usage of colour balls is featured. Dynamics of hits for baseball players on a flying ball is presented. The approach in modelling of requirements of competitive activity is developed.

Pearl Harbor: A Failure for Baseball?

Science.gov (United States)

Crepeau, Richard C.

The history of sports is closely tied to the larger history of the society in which they are played. Baseball in the United States in the 1920's and l930's assumed a major role in spreading the ideals of fair play, sportsmanship, and democracy to the Far East, with tours by amateur athletes and professionals such as Lou Gehrig and Babe Ruth. Even…

Large high current density superconducting solenoids for use in high energy physics experiments

International Nuclear Information System (INIS)

Green, M.A.; Eberhard, P.H.; Taylor, J.D.

1976-05-01

Very often the study of high energy physics in colliding beam storage-rings requires a large magnetic field volume in order to detect and analyze charged particles which are created from the collision of two particle beams. Large superconducting solenoids which are greater than 1 meter in diameter are required for this kind of physics. In many cases, interesting physics can be done outside the magnet coil, and this often requires that the amount of material in the magnet coil be minimized. As a result, these solenoids should have high current density (up to 10 9 A m -2 ) superconducting windings. The methods commonly used to stabilize large superconducting magnets cannot be employed because of this need to minimize the amount of material in the coils. A description is given of the Lawrence Berkeley Laboratory program for building and testing prototype solenoid magnets which are designed to operate at coil current densities in excess of 10 9 A m -2 with magnetic stored energies which are as high as 1.5 Megajoules per meter of solenoid length. The coils use intrinsically stable multifilament Nb--Ti superconductors. Control of the magnetic field quench is achieved by using a low resistance aluminum bore tube which is inductively coupled to the coil. The inner cryostat is replaced by a tubular cooling system which carries two phase liquid helium. The magnet coil, the cooling tubes, and aluminum bore tube are cast in epoxy to form a single unified magnet and cryogenic system which is about 2 centimeters thick. The results of the magnet coil tests are discussed

The state of superconductivity

International Nuclear Information System (INIS)

Clark, T.D.

1981-01-01

The present status of applications based on the phenomena of superconductivity are reviewed. Superconducting materials, large scale applications, the Josephson effect and its applications, and superconductivity in instrumentation, are considered. The influence that superconductivity has had on modern theories of elementary particles, such as gauge symmetry breaking, is discussed. (U.K.)

Organic superconductivity

International Nuclear Information System (INIS)

Jerome, D.

1980-01-01

We present the experimental evidences for the existence of a superconducting state in the Quasi One Dimensional organic conductor (TMTSF) 2 PF 6 . Superconductivity occuring at 1 K under 12 kbar is characterized by a zero resistance diamagnetic state. The anistropy of the upper critical field of this type II superconductor is consistent with the band structure anistropy. We present evidences for the existence of large superconducting precursor effects giving rise to a dominant paraconductive contribution below 40 K. We also discuss the anomalously large pressure dependence of T sb(s), which drops to 0.19 K under 24 kbar in terms of the current theories. (author)

The Kinetics of Swinging a Baseball Bat.

Science.gov (United States)

Crisco, Joseph J; Osvalds, Nikolas J; Rainbow, Michael J

2018-04-13

The purpose of this study was to compute the three-dimensional kinetics required to swing three youth baseball bats of varying moments of inertia (MOI). 306 swings by 22 male players (13-18 yrs.) were analyzed. Inverse dynamics with respect to the batter's hands were computed given the known kinematics and physical properties of the bats. We found that peak force increased with larger bat MOI and was strongly correlated with bat tip speed. In contrast, peak moments were weakly correlated with bat MOI and bat tip speed. Throughout the swing, the force applied to the bat was dominated by a component aligned with the long axis of the bat and directed away from the bat knob, while the moment applied to the bat was minimal until just prior to ball impact. These results indicate that players act to mostly "pull" the bat during their swing until just prior to ball impact, at which point they rapidly increase the moment on the bat. This kinetic analysis provides novel insight into the forces and moments used to swing baseball bats.

Pioneering superconducting magnets in large tokamaks: evaluation after 16 years of operating experience in tore supra

International Nuclear Information System (INIS)

Duchateau, J.L.; Gravil, B.; Tena, E.; Henry, D.; Journeaux, J.Y.; Libeyre, P.

2004-01-01

The toroidal field (TF) system of Tore Supra (TS) is superconducting. After 16 years of operation it is possible to give an overview of the experience gained on a large superconducting system integrated in a large Tokamak. Quantitative data will be given, about the TF system for the cryogenic system and for the magnet system as well, concerning the number of plasmas shots and the availability of the machine. The origin and the number of breakdowns or incidents will be described, with emphasis on cryogenics, to document repairs and changes on the system components. Concerning the behaviour during operation, the Fast Safety Discharges (FSD) in operation are of particular interest for the Tokamak operation, as they interrupt it on a significant time of the order of one hour. This aspect is particularly documented. The approach followed to decrease the number of these FSD will be reported and explained. The Tore Supra Tokamak was the first important meeting between Superconductivity and Plasma Physics on a large scale. Overall, despite the differences in design and size, the accumulated experience over 16 years of operation is a useful tool to prepare the manufacturing and the operation of the ITER magnets. (authors)

Advanced superconducting technology for global science: The Large Hadron Collider at CERN

Science.gov (United States)

Lebrun, Ph.

2002-05-01

The Large Hadron Collider (LHC), presently in construction at CERN, the European Organization for Nuclear Research near Geneva (Switzerland), will be, upon its completion in 2005 and for the next twenty years, the most advanced research instrument of the world's high-energy physics community, providing access to the energy frontier above 1 TeV per elementary constituent. Re-using the 26.7-km circumference tunnel and infrastructure of the past LEP electron-positon collider, operated until 2000, the LHC will make use of advanced superconducting technology-high-field Nb-Ti superconducting magnets operated in superfluid helium and a cryogenic ultra-high vacuum system-to bring into collision intense beams of protons and ions at unprecedented values of center-of-mass energy and luminosity (14 TeV and 1034 cm-2ṡs-1, respectively with protons). After some ten years of focussed R&D, the LHC components are presently series-built in industry and procured through world-wide collaboration. After briefly recalling the physics goals, performance challenges and design choices of the machine, we describe its major technical systems, with particular emphasis on relevant advances in the key technologies of superconductivity and cryogenics, and report on its construction progress.

Development of superconducting links for the Large Hadron Collider machine

Science.gov (United States)

Ballarino, Amalia

2014-04-01

In the framework of the upgrade of the Large Hadron Collider (LHC) machine, new superconducting lines are being developed for the feeding of the LHC magnets. The proposed electrical layout envisages the location of the power converters in surface buildings, and the transfer of the current from the surface to the LHC tunnel, where the magnets are located, via superconducting links containing tens of cables feeding different circuits and transferring altogether more than 150 kA. Depending on the location, the links will have a length ranging from 300 m to 500 m, and they will span a vertical distance of about 80 m. An overview of the R&D program that has been launched by CERN is presented, with special attention to the development of novel types of cables made from MgB2 and high temperature superconductors (Bi-2223 and REBCO) and to the results of the tests performed on prototype links. Plans for future activities are presented, together with a timeline for potential future integration in the LHC machine.

Development of superconducting links for the Large Hadron Collider machine

CERN Document Server

Ballarino, A

2014-01-01

In the framework of the upgrade of the Large Hadron Collider (LHC) machine, new superconducting lines are being developed for the feeding of the LHC magnets. The proposed electrical layout envisages the location of the power converters in surface buildings, and the transfer of the current from the surface to the LHC tunnel, where the magnets are located, via superconducting links containing tens of cables feeding different circuits and transferring altogether more than 150 kA. Depending on the location, the links will have a length ranging from 300 m to 500 m, and they will span a vertical distance of about 80 m. An overview of the R&D program that has been launched by CERN is presented, with special attention to the development of novel types of cables made from MgB 2 and high temperature superconductors (Bi-2223 and REBCO) and to the results of the tests performed on prototype links. Plans for future activities are presented, together with a timeline for potential future integration in the LHC machine.

Shoulder joint velocity during fastball pitching in baseball

NARCIS (Netherlands)

Gasparutto, X.; van der Graaff, E; van der Helm, F.C.T.; Veeger, H.E.J.; Colloud, F.; Domalain, M.; Monnet, T.

2015-01-01

The purpose of this study was to assess the rotation and translation velocity of the shoulder complex during fastball pitching in baseball. 8 pitchers from the Dutch AAA team performed each 3 fastball pitches. Their motion was recorded by an opto-electronic device. Kinematic computation was

A new cryogenic test facility for large superconducting devices at CERN

CERN Document Server

Perin, A; Serio, L; Stewart, L; Benda, V; Bremer, J; Pirotte, O

2015-01-01

To expand CERN testing capability to superconducting devices that cannot be installed in existing test facilities because of their size and/or mass, CERN is building a new cryogenic test facility for large and heavy devices. The first devices to be tested in the facility will be the S-FRS superconducting magnets for the FAIR project that is currently under construction at the GSI Research Center in Darmstadt, Germany. The facility will include a renovated cold box with 1.2 kW at 4.5 K equivalent power with its compression system, two independent 15 kW liquid nitrogen precooling and warm-up units, as well as a dedicated cryogenic distribution system providing cooling power to three independent test benches. The article presents the main input parameters and constraints used to define the cryogenic system and its infrastructure. The chosen layout and configuration of the facility is presented and the characteristics of the main components are described.

Curve ball baseball, statistics, and the role of chance in the game

CERN Document Server

Bennett, Jay

2001-01-01

In its formative years, from the 1970s through the 1990s, sabermetrics was p- marily an amateur undertaking. Publications were aimed at a relatively small audience of baseball fans. To be sure, this ever-growing group of aficionados brought a lot of sophistication to baseball analysis, and were constantly looking for statistical insights beyond the listings of the top ten batters found in popular newspapers and magazines. But their influence on the baseball profession was very limited. A few consultants like Craig Wright developed temporary relati- ships with various teams, but none were able to stay long enough to create a p- manent sabermetrician staff position. (See Rob Neyer’s November 11, 2002, arti- 1 cle on ESPN. com. ) All of this changed, however, in 2002 with the hiring of Bill James by the Boston Red Sox. With that move, we have seen the admittance of the foremost proponent of sabermetrics into the top echelon of professional ba- ball management. The art and science of careful statistical analysi...

Unusually large magnetic moments in the normal state and superconducting state of Sn nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Hung, Chi-Hang; Lee, Chi-Hung; Hsu, Chien-Kang; Li, Chi-Yen; Karna, Sunil K.; Wang, Chin-Wei; Wu, Chun-Ming; Li, Wen-Hsien, E-mail: whli@phy.ncu.edu.tw [National Central University, Department of Physics and Center for Neutron Beam Applications (China)

2013-09-15

We report on the observations of spontaneous magnetic moments in the normal as well as in the superconducting states of a 9 nm Sn nanoparticle assembly, through X-ray diffraction, magnetization, ac magnetic susceptibility, and neutron diffraction measurements. The saturation magnetization reaches an unexpectedly large value of 1.04 emu/g at 5 K, with a temperature profile that can be described by Bloch's law with an exponent of b = 1.8. A magnetic moment of Left-Pointing-Angle-Bracket {mu}{sub Z} Right-Pointing-Angle-Bracket = 0.38 {mu}{sub B} develops after cooling from 260 to 4 K. Superconductivity develops below T{sub C} = 3.98 K, which is 7 % higher than the T{sub C} = 3.72 K of bulk Sn. Surprisingly, an addition magnetic moment of Left-Pointing-Angle-Bracket {mu}{sub Z} Right-Pointing-Angle-Bracket = 0.05 {mu}{sub B} develops upon entering the superconducting state.

Conceptual design and development of a superconducting bus-line for the Large Helical Device

International Nuclear Information System (INIS)

Mito, T.; Takahata, K.; Yamada, S.; Yamamoto, J.; Uede, T.; Ikeda, M.

1993-01-01

A superconducting bus-line is proposed and preliminarily tested as an electrical feeder between the superconducting coils of the Large Helical Device (LHD) and their electrical power supply. The bus-line consists of a superconductor and its cryogenic transfer-line. The superconductor is a specially developed aluminum stabilized NbTi wire, which is installed in the innermost channel of the transfer-line. The vacuum insulated transfer-line consists of four corrugated tubes assembled coaxially. Liquid helium flows through the innermost channel and shield gas flows through another annular channel in the line. We are completing the conceptual design of the bus-line and the installation plan for the LHD experimental hall and are carrying out development of wires, including an investigation of their mechanical properties and electrical insulation. This report describes the conceptual design of the superconducting bus-line for the LHD, and the results we obtained recently during the design and development of a full-scale demonstration facility. (orig.)

Effect of education and language on baseline concussion screening tests in professional baseball players.

Science.gov (United States)

Jones, Nathaniel S; Walter, Kevin D; Caplinger, Roger; Wright, Daniel; Raasch, William G; Young, Craig

2014-07-01

The purpose of the present study was to investigate the possible effects of sociocultural influences, specifically pertaining to language and education, on baseline neuropsychological concussion testing as obtained via immediate postconcussion assessment and cognitive testing (ImPACT) of players from a professional baseball team. A retrospective chart review. Baseline testing of a professional baseball organization. Four hundred five professional baseball players. Age, languages spoken, hometown country location (United States/Canada vs overseas), and years of education. The 5 ImPACT composite scores (verbal memory, visual memory, visual motor speed, reaction time, impulse control) and ImPACT total symptom score from the initial baseline testing. The result of t tests revealed significant differences (P education, the significant differences (P < 0.05) remained in some scores. Sociocultural differences may result in differences in computer-based neuropsychological testing scores.

An Epidemiological Comparison of Elbow Injuries Among United States High School Baseball and Softball Players, 2005-2006 Through 2014-2015.

Science.gov (United States)

Pytiak, Andrew V; Kraeutler, Matthew J; Currie, Dustin W; McCarty, Eric C; Comstock, R Dawn

Pitching is a common mechanism of injury in baseball, with known risk factors for elbow injuries among adolescent pitchers. Elbow injury rates and mechanisms will differ between high school baseball and softball players. Descriptive epidemiology study. Level 3. Baseball- and softball-related injury data from the 2005-2006 through 2014-2015 academic years were collected from the High School Reporting Information Online (RIO) Internet-based data collection tool. Athlete-exposure (AE) and injury data were collected by certified athletic trainers. Rate ratios (RRs) were calculated comparing injury rates in the 2 populations. Injury proportion ratios (IPRs) comparing elbow injuries in pitchers and nonpitchers were calculated as the proportion of all elbow injuries in pitchers divided by the proportion of all elbow injuries in nonpitchers. A total of 214 elbow injuries in male baseball players occurred over 2,327,774 AEs, for an overall elbow injury rate of 0.92 per 10,000 AEs. A total of 75 elbow injuries were reported in female softball players over 1,731,644 AEs, for an overall rate of 0.43 per 10,000 AEs. The rate of elbow injury was significantly higher for baseball than softball (RR, 2.12; 95% CI, 1.64-2.77). A significantly greater proportion of elbow injuries in baseball were pitching-related compared with those from softball, with 50.2% occurring while pitching in baseball versus 11.0% in softball (IPR, 4.58; 95% CI, 2.35-8.93). If all injuries occurring during pitching were removed from both sports, the difference in elbow injury rate for baseball and softball would no longer be significant (RR, 1.19; 95% CI, 0.88-1.62). The rate of elbow injuries is significantly higher in baseball than softball. This is attributable to differences in rates of pitching-related injuries between these 2 groups. These results demonstrate that overhand pitching increases risk of elbow injury in high school athletes.

Pioneering superconducting magnets in large tokamaks: Evaluation after 16 years of operating experience in tore supra

International Nuclear Information System (INIS)

Libeyre, P.; Duchateau, J.L.; Gravil, B.; Tena, E.; Henry, D.; Journeaux, J.Y.

2005-01-01

The toroidal field (TF) system of TORE SUPRA (TS) is superconducting. After 16 years of operation it is possible to give an overview of the experience gained on a large superconducting system integrated in a large Tokamak. Quantitative data will be given, about the TF system for the cryogenic system and for the magnet system as well, concerning the number of plasmas shots and the availability of the machine. The origin and the number of breakdowns or incidents will be described, with emphasis on cryogenics and associated repairs and changes on the system components along the time. As concerns the behaviour during operation, the fast safety discharges (FSD) in operation are of particular interest for the Tokamak operation, as they interrupt it for a significant time of the order of 1 h. This aspect is particularly documented. The approach followed to decrease the number of these FSD will be reported and explained. The TORE SUPRA Tokamak was the first important application of superconductivity in plasma physics on a large scale. Overall, despite the differences in design and size, the accumulated experience over 16 years of operation is a useful tool to prepare the manufacture and the operation of the ITER magnets

Future IBM-BNL large-area superconducting inductive monopole detectors

International Nuclear Information System (INIS)

Bermon, S.; Chi, C.C.; Tsuei, C.C.; Chaudhari, P.; Ketchen, M.; Tesche, C.D.; Prodell, A.

1986-01-01

The observation of massive moving magnetic monopoles would have extremely important implications for grand unification theories and cosmological models for the creation of the universe. Among detection methods, the superconducting induction technique is unique in that it directly and unambiguously measures the sole property of the monopole of which the authors are certain--its magnetic charge--the detector response being independent of all other characteristics such as the monopole mass, its velocity, the presence of a companion electric charge, or the detailed nature of its interaction with matter. Described herein are plans for constructing an induction detector sufficiently large to reach the Parker bound in several years of operation

Advanced superconducting technology for global science: The Large Hadron Collider at CERN

International Nuclear Information System (INIS)

Lebrun, Ph.

2002-01-01

The Large Hadron Collider (LHC), presently in construction at CERN, the European Organization for Nuclear Research near Geneva (Switzerland), will be, upon its completion in 2005 and for the next twenty years, the most advanced research instrument of the world's high-energy physics community, providing access to the energy frontier above 1 TeV per elementary constituent. Re-using the 26.7-km circumference tunnel and infrastructure of the past LEP electron-positon collider, operated until 2000, the LHC will make use of advanced superconducting technology-high-field Nb-Ti superconducting magnets operated in superfluid helium and a cryogenic ultra-high vacuum system-to bring into collision intense beams of protons and ions at unprecedented values of center-of-mass energy and luminosity (14 TeV and 10 34 cm -2 ·s -1 , respectively with protons). After some ten years of focussed R and D, the LHC components are presently series-built in industry and procured through world-wide collaboration. After briefly recalling the physics goals, performance challenges and design choices of the machine, we describe its major technical systems, with particular emphasis on relevant advances in the key technologies of superconductivity and cryogenics, and report on its construction progress

The Epidemiology of Hip and Groin Injuries in Professional Baseball Players.

Science.gov (United States)

Coleman, Struan H; Mayer, Stephanie W; Tyson, Jared J; Pollack, Keshia M; Curriero, Frank C

2016-01-01

Injuries of the hip and groin among professional baseball players can result in a significant number of disabled list days. The epidemiology of these injuries has not been delineated. The purpose of this study is to describe the incidence, mechanism, type, and rehabilitation course of hip and groin injuries among Major League Baseball (MLB) and Minor League Baseball (MiLB) players. The MLB injury database for hip and groin injuries from 2011-2014 was analyzed. Occurrence of injuries was assessed based on level of play, field location, activity during which the injury occurred, mechanism of injury, and days missed. The treatment was recorded as nonoperative or surgical. The subsequent rehabilitation and return to play were recorded. Chi-square tests were used to test the hypothesis of equal proportions between the various categories of hip and groin characteristics. From 2011-2014, 1823 hip and groin injuries occurred among MLB and MiLB players, which accounted for approximately 5% of all injuries. Of these, 1514 (83%) occurred among MiLB players and 309 (17%) among MLB players; 96% of injuries were extra-articular. Among all players, a noncontact mechanism during defensive fielding was the most common activity causing injury (74%), and infielders experienced the most hip and groin injuries (34%). The majority of extra-articular injuries were treated nonoperatively (96.2%), resulting in an average of 12 days missed. Intra-articular pathology more commonly required surgery, and resulted in an average of 123 days missed. Hip and groin injuries can be debilitating and result in a significant number of days missed. Intra-articular pathology and athletic pubalgia were usually treated surgically, while the majority of extra-articular hip injuries were treated successfully with nonoperative modalities. Correct diagnosis and appropriate treatment can lead to a high rate of return to play for professional baseball players with injuries to the hip and groin.

Systematic Review of Traumatic Brain Injuries in Baseball and Softball: A Framework for Prevention

Directory of Open Access Journals (Sweden)

Michael D. Cusimano

2017-10-01

Full Text Available BackgroundTraumatic brain injuries (TBIs are an important public health challenge. The classification of baseball and softball as low contact sports and their association with extremity injuries cause individuals to overlook the risk of TBI in baseball and softball.PurposeTo summarize our knowledge of the epidemiology and risk factors of TBIs associated with baseball and softball with an aim to better design and implement preventive strategies.MethodsA search algorithm containing keywords that were synonymous to the terms “TBI,” “baseball” was applied to the following nine databases: MEDLINE, Scopus, PubMed, EMBASE, CINAHL, Healthstar, PsychINFO, AMED, Cochrane library. Cited reference lists of identified articles were also consulted yielding a total of eighty-eight articles for full review. The search was concluded on November 14, 2016. The level of evidence was evaluated according to the guidelines from Strengthening the Reporting of Observational Studies in Epidemiology statement.ResultsTwenty-nine articles published between 2000 and 2016 met the criteria for analysis. Collectively, they examined the years 1982–2015 and identified 242,731 baseball-and softball-related TBIs. The most explored outcome of TBI was concussion. The average injury rate per 1,000 athletic exposures was 0.13 (range 0.03–0.46. The most common mechanism of injury was being struck by bat for younger players and being struck by ball for older athletes (adolescent and beyond. Rates of TBI were on average 4.17 times greater in games compared to practices. Females were on average 2.04 times more likely to sustain a TBI than males. Severity of TBIs varied considerably from mild and returning to the field on the same day, to immediate death. Generally, there is poor compliance with helmet use and return-to-play post-concussion guidelines. An increase TBI rates was observed over time. Multifaceted preventive strategies must be implemented to reduce the frequency and

Using Statistical Process Control Charts to Identify the Steroids Era in Major League Baseball: An Educational Exercise

Science.gov (United States)

Hill, Stephen E.; Schvaneveldt, Shane J.

2011-01-01

This article presents an educational exercise in which statistical process control charts are constructed and used to identify the Steroids Era in American professional baseball. During this period (roughly 1993 until the present), numerous baseball players were alleged or proven to have used banned, performance-enhancing drugs. Also observed…

Swing Weights of Baseball and Softball Bats

Science.gov (United States)

Russell, Dan

2010-01-01

Baseball and softball bats are sold according to length in inches and weight in ounces. Much to the consternation of players buying new bats, however, not all bats that weigh the same swing the same. The reason for this has to do with moment of inertia of the bat about a pivot point on the handle, or what the sporting goods industry refers to as…

Control of field uniformity for a large superconducting storage ring magnet

International Nuclear Information System (INIS)

Danby, G.T.; Jackson, J.W.

1994-01-01

A 1.45 Tesla, 14.2 meter diameter ''superferric'' magnet is in an advanced stage of construction at BNL. This magnet will be used to store muons for a planned ultra-precise measurement of their anomalous magnetic moment g-2. This measurement requires a magnetic field uniformity of 1 PPM with a knowledge of the field over the muon orbits to 0.1 PPM. The methods built into the design to produce ultra-high field uniformity will be described. Large deviations from the ideal circularly symmetric uniform shape of the iron flux path are required to accommodate transfer lines and superconducting current leads, as well as apparatus for beam injection. Shimming methods to correct for the perturbations due to these large holes will be presented. The pole pieces consist of 36 closely fitting 10 degree arc sections butted together to produce a very good approximation to a continuous 360 degree ring magnet. However, in the cast of a possible quench of the superconducting coils, significant eddy currents will be induced which will circulate within the confines of each 10 degree pole piece. At the great precision required, these eddy currents may leave very small but significant aberrations in the field even after they decay away, because of slight changes in the orientation of the magnetization. Surface coil possibilities to correct for this effect will be described

Performance of a superconducting large-angle magnetic suspension

International Nuclear Information System (INIS)

Downer, J.R.; Bushko, D.A.; Gondhalekar, V.; Torti, R.P.

1992-01-01

SatCon Technology Corporation is working toward the development of an advanced-concept Control Moment Gyro (CMG). The advanced-concept CMG is sized for use as a slewing actuator for large space-based payloads. The design features a magnetically suspended composite rotor which contains a persistent-mode superconducting solenoid magnet. The rotor is suspended and gimballed by the interaction of the fields produced by the superconductor and an array of cryoresistive coils. The rotor spins in a liquid helium environment, while the control coils are liquid-hydrogen cooled. This design is capable of meeting the requirements of many high-performance slewing applications (27,000 Nm). The use of the magnetic suspension as rotor bearings, gimbal bearings, and gimbal torquers also substantially reduces the mass of the CMG system

Leadership styles of elite Dixie youth baseball coaches.

Science.gov (United States)

Bennett, G; Maneval, M

1998-12-01

Chelladurai and Saleh's Leadership Scale for Sports was administered to 52 elite Dixie Youth baseball coaches. Analyses indicated that subjects scored high in positive feedback, training and instruction, and social support, moderate in democratic behavior, and low in autocratic behavior. These results seem to support the validity of using the scale to compare coaching behavior.

Development of superconducting poloidal field coils for medium and large size tokamaks

International Nuclear Information System (INIS)

Dittrich, H.-G.; Forster, S.; Hofmann, A.

1983-01-01

Large long pulse tokamak fusion experiments require the use of superconducting poloidal field (PF) coils. In the past not much attention has been paid to the development of such coils. Therefore a development programme has been initiated recently at KfK. In this report start with summarizing the relevant PF coil parameters of some medium and large size tokamaks presently under construction or design, respectively. The most important areas of research and development work are deduced from these parameters. Design considerations and first experimental results concerning low loss conductors, cooling concepts and structural components are given

Baseball II-T, a new target plasma startup experiment

International Nuclear Information System (INIS)

Chargin, A.; Denhoy, B.; Frank, A.; Thomas, S.

1975-01-01

A brief description is given of modifications and additions to the existing Baseball II experiment. These changes will make it possible to study target plasma buildup in a steady-state magnetic field. This experiment, now called Baseball II-T + will use a pellet generator to deliver ammonia pellets into the center of the magnetic mirror field where they will be heated with a 300-J, 50-ns, CO 2 laser. The plasma created by this method will have a density of approximately 10 13 cm -3 and a temperature of about 1 keV. This target plasma will be used for neutral beam injection startup studies with a 50-A, 20-keV neutral beam. Later, the beam power will be increased to study buildup. With ion injection energies of up to 50 keV, it may be possible to achieve etatau as high as 10 12 cm -3 s. The new components necessary to achieve these goals are described

Large-scale applications of superconductivity in the United States: an overview. Metallurgy, fabrication, and applications

International Nuclear Information System (INIS)

Hein, R.A.; Gubser, D.U.

1981-01-01

This report presents an overview of ongoing development efforts in the USA concerned with large-scale applications of superconductivity. These applications are grouped according to magnetic field regime, as low field regime, intermediate field regime, and high field regime. In the low field regime two diverse areas of large application are identified, superconducting power transmission lines for electric utilities, and RF cavities for particle accelerators for high energy physics research. Activity in the intermediate regime has been significantly increased due to Fermilab's energy doubler or Tevatron project, and BNL's ISABELLE project. Rotating electrical machines, such as DC acyclic (homopolar) motors, generators, and energy storage magnets are also studied. In the high field regime magnetohydrodynamics (MHD) and magnetically confined fusion in tokamaks are examined. In each regime all current work is summarized according to key person, research topic, type of program, funding, status, and future outlook

Superconductivity application technologies. Superconducting quadrupole magnet and cooling system for KEK B factory

International Nuclear Information System (INIS)

Tsuchiya, Kiyosumi; Yamaguchi, Kiyoshi; Sakurabata, Hiroaki; Seido, Masahiro; Matsumoto, Kozo.

1997-01-01

At present in National Laboratory for High Energy Physics (KEK), the construction of B factory is in progress. By colliding 8 GeV electrons and 3.5 GeV positrons, this facility generates large amounts of B mesons and anti-B mesons, and performs the elementary particle experiment of high accuracy. It is the collision type accelerator of asymmetric two-ring type comprising 8 GeV and 3.5 GeV rings. In the field of high energy physics, superconductivity technology has been put to practical use. As the objects of superconductivity technology, there are dipole magnet for bending beam, quadrupole magnet for adjusting beam, large solenoid magnet used for detector and so on. Superconducting magnets which are indispensable for high energy, superconducting wire material suitable to accelerators, and the liquid helium cooling system for maintaining superconducting magnets at 4.4 K are reported. The technologies of metallic conductors and making their coils have advanced rapidly, and also cooling technology has advanced, accordingly, superconductivity technology has reached the stage of practical use perfectly. (K.I.)

Advanced Superconducting Technology for Global Science The Large Hadron Collider at CERN

CERN Document Server

Lebrun, P

2002-01-01

The Large Hadron Collider (LHC), presently in construction at CERN, the European Organisation for Nuclear Research near Geneva (Switzerland), will be, upon its completion in 2005 and for the next twenty years, the most advanced research instrument of the world's high-energy physics community, providing access to the energy frontier above 1 TeV per elementary constituent. Re-using the 26.7-km circumference tunnel and infrastructure of the past LEP electron-positon collider, operated until 2000, the LHC will make use of advanced superconducting technology - high-field Nb-Ti superconducting magnets operated in superfluid helium and a cryogenic ultra-high vacuum system - to bring into collision intense beams of protons and ions at unprecedented values of center-of-mass energy and luminosity (14 TeV and 1034 cm-2.s-1, respectively with protons). After some ten years of focussed R&D, the LHC components are presently series-built in industry and procured through world-wide collaboration. After briefly recalling ...

Construction program for a large superconducting MHD magnet system at the coal-fired flow facility

International Nuclear Information System (INIS)

Wang, S.T.; Genens, L.; Gonczy, J.; Ludwig, H.; Lieberg, M.; Kraft, E.; Gacek, D.; Huang, Y.C.; Chen, C.J.

1980-01-01

The Argonne National Laboratory has designed and is constructing a 6 T large aperture superconducting MHD magnet for use in the Coal-Fired Flow Facility (CFFF) at the University of Tennessee Space Institute (UTSI) at Tullahoma, Tennessee. The magnet system consists of the superconducting magnet, a magnet power supply, an integrated instrumentation for operation, control and protection, and a complete cryogenic facility including a CTI Model 2800 helium refrigerator/liquefier with two compressors, helium gas handling system and a 7500 liter liquid helium dewar. The complete system will be tested at Argonne, IL in 1981. The magnet design is reviewed, and the coil fabrication programs are described in detail

Enhanced superconductivity of fullerenes

Energy Technology Data Exchange (ETDEWEB)

Washington, II, Aaron L.; Teprovich, Joseph A.; Zidan, Ragaiy

2017-06-20

Methods for enhancing characteristics of superconductive fullerenes and devices incorporating the fullerenes are disclosed. Enhancements can include increase in the critical transition temperature at a constant magnetic field; the existence of a superconducting hysteresis over a changing magnetic field; a decrease in the stabilizing magnetic field required for the onset of superconductivity; and/or an increase in the stability of superconductivity over a large magnetic field. The enhancements can be brought about by transmitting electromagnetic radiation to the superconductive fullerene such that the electromagnetic radiation impinges on the fullerene with an energy that is greater than the band gap of the fullerene.

The Use of Ice in Baseball Injuries (Cryotherapy).

Science.gov (United States)

Suspenski, Thomas J.

Cryotherapy (the use of ice and exercise to rehabilitate athletic injuries) can be an effective method of treating baseball injuries. It is generally agreed that ice is appropriate for the first 24 to 48 hours, but there is disagreement over its use beyond 72 hours. Some physicians and trainers support the use of heat with either exercise or rest,…

Major League Baseball Anti-Trust Immunity: Examining the Legal and Financial Implications of Relocation Rules

OpenAIRE

Mark, Nagel; Matt, Brown; Daniel, Rascher; Chad, McEvoy

2006-01-01

Major League Baseball (MLB) rules restrict the movement of any franchise into another’s territory. These territorial rules are designed to protect each team’s potential local revenue sources as well as to provide stability throughout the league. Recently, Major League Baseball approved financial compensation for the Washington Nationals’ move into the Baltimore Orioles’ territory – primarily because it was in the best interest of MLB even though it hurt the Orioles. However, the Oakland Athle...

Kinematic and Kinetic Profiles of Trunk and Lower Limbs during Baseball Pitching in Collegiate Pitchers

Directory of Open Access Journals (Sweden)

Masahiro Kageyama, Takashi Sugiyama, Yohei Takai, Hiroaki Kanehisa, Akira Maeda

2014-12-01

Full Text Available The purpose of this study was to clarify differences in the kinematic and kinetic profiles of the trunk and lower extremities during baseball pitching in collegiate baseball pitchers, in relation to differences in the pitched ball velocity. The subjects were 30 collegiate baseball pitchers aged 18 to 22 yrs, who were assigned to high- (HG, 37.4 ± 0.8 m·s-1 and low-pitched-ball-velocity groups (LG, 33.3 ± 0.8 m·s-1. Three-dimensional motion analysis with a comprehensive lower-extremity model was used to evaluate kinematic and kinetic parameters during baseball pitching. The ground-reaction forces (GRF of the pivot and stride legs during pitching were determined using two multicomponent force plates. The joint torques of hip, knee, and ankle were calculated using inverse-dynamics computation of a musculoskeletal human model. To eliminate any effect of variation in body size, kinetic and GRF data were normalized by dividing them by body mass. The maxima and minima of GRF (Fy, Fz, and resultant forces on the pivot and stride leg were significantly greater in the HG than in the LG (p < 0.05. Furthermore, Fy, Fz, and resultant forces on the stride leg at maximum shoulder external rotation and ball release were significantly greater in the HG than in the LG (p < 0.05. The hip abduction, hip internal rotation and knee extension torques of the pivot leg and the hip adduction torque of the stride leg when it contacted the ground were significantly greater in the HG than in the LG (p < 0.05. These results indicate that, compared with low-ball-velocity pitchers, high-ball-velocity pitchers can generate greater momentum of the lower limbs during baseball pitching.

Superconductivity in technology

International Nuclear Information System (INIS)

Komarek, P.

1976-01-01

Physics, especially high energy physics and solid state physics was the first area in which superconducting magnets were used but in the long run, the most extensive application of superconductivity will probably be in energy technology. Superconducting power transmission cables, magnets for energy conversion in superconducting electrical machines, MHD-generators and fusion reactors and magnets for energy storage are being investigated. Magnets for fusion reactors will have particularly large physical dimensions, which means that much development effort is still needed, for there is no economic alternative. Superconducting surfaces in radio frequency cavities can give Q-values up to a factor of 10 6 higher than those of conventional resonators. Particle accelerators are the important application. And for telecommunication, simple coaxial superconducting radio frequency cables seem promising. The tunnel effect in superconducting junctions is now being developed commercially for sensitive magnetometers and may soon possibly feature in the memory cells of computer devices. Hence superconductivity can play an important role in the technological world, solving physical and technological problems and showing economic advantages as compared with possible conventional techniques, bearing also in mind the importance of reliability and safety. (author)

Superconductivity and its application

International Nuclear Information System (INIS)

Spadoni, M.

1988-01-01

This paper, after a short introduction to superconductivity and to multifilamentary superconducting composites is aiming to review the state of the art and the future perspective of some of the applications of the superconducting materials. The main interest is focussed to large scale applications like, for istance, magnets for accelerators or fusion reactors, superconducting system for NMR thomography, etc. A short paragraph is dedicated to applications for high sensitivity instrumentation. The paper is then concluded by some considerations about the potentialities of the newly discovered high critical temperature materials

The effect of ocular dominance on the performance of professional baseball players.

Science.gov (United States)

Laby, D M; Kirschen, D G; Rosenbaum, A L; Mellman, M F

1998-05-01

The purpose of the study was to determine whether a performance difference exists between baseball players with "same" (right-right) and "crossed" (right-left) hand-ocular dominance. A cohort study design was used. Four hundred and ten major and minor league members of the Los Angeles Dodgers professional baseball team. Measurement of ocular dominance. Batting average and earned run average (ERA). Same/crossed dominance (with P values in parentheses) are as follows: Batting averages: major league-0.271/0.251 (0.20); minor league-0.274/0.270 (0.57); ERA: major league-3.34/3.56 (0.66); minor league-4.00/4.20 (0.54). Hand-ocular dominance patterns do not have an effect on batting average or ERA.

Investigating customer racial discrimination in the secondary baseball card market.

Science.gov (United States)

Primm, Eric; Piquero, Nicole Leeper; Piquero, Alex R; Regoli, Robert M

2011-01-01

A growing body of literature in a variety of disciplines has appeared over the last 20 years examining customer racial bias in the secondary sports card market; however, consensus on the matter has yet to emerge. In this article, we explore the more subtle ways that a player's race/ethnicity may affect the value of his sports card including a player's skin tone (light- to dark-skinned). Data were obtained for 383 black, Latino, and white baseball players who had received at least one vote for induction into Major League Baseball's Hall of Fame including their career performance statistics, rookie card price, card availability, Hall of Fame status, and skin tone. Findings indicate that card availability is the primary determinant of card value while a player's skin tone has no direct effect. Subsequent analysis demonstrates that a player's race (white/non-white) rather than skin tone did have an effect as it interacts with Hall of Fame status to influence his rookie card price.

Drive theory and home run milestones in baseball: an historical analysis.

Science.gov (United States)

Goldschmied, Nadav; Harris, Michael; Vira, Damien; Kowalczyk, Jason

2014-02-01

The purpose of this investigation was to test whether the performance of the home run hitters in Major League Baseball adhered to predictions of Drive Theory. 24 baseball players who have hit at least 505 home runs were included in the sample. Their performance was assessed around the time in which they reached a significant home run career milestone, operationalized as either 500 or 600 home runs, or surpassing the league's home run record. As predicted, the players were found to require significantly more at-bats to complete the 5 home runs before the milestone, when stress was assumed to be mounting, than the 5 home runs after the milestone. In contrast, those players who reached the personal landmark from 1988 (the suspected commencement of the so-called "Steroid Era") onwards required the same number of at-bats before and after the milestone.

On anyon superconductivity--

International Nuclear Information System (INIS)

Chen, Y.-H.; Wilczek, F.; Witten, E.; Halperin, B.I.

1989-01-01

We investigate the statistical mechanics of a gas of fractional statistics particles in 2 + 1 dimensions. In the case of statistics very close to Fermi statistics (statistical parameter θ = π(1 - 1/n), for large n), the effect of the statistics is a weak attraction. Building upon earlier RPA calculation for the case n = 2, the authors argue that for large n perturbation theory is reliable and exhibits superfluidity (or superconductivity after coupling to electromagnetism). They describe the order parameter for this superconductng phase in terms of spontaneous breaking of commutativity of translations as opposed to the usual pairing order parameters. The vortices of the superconducting anyon gas are charged, and superconducting order parameters of the usual type vanish. They investigate the characteristic P and T violating phenomenology

Design of shared instruments to utilize simulated gravities generated by a large-gradient, high-field superconducting magnet.

Science.gov (United States)

Wang, Y; Yin, D C; Liu, Y M; Shi, J Z; Lu, H M; Shi, Z H; Qian, A R; Shang, P

2011-03-01

A high-field superconducting magnet can provide both high-magnetic fields and large-field gradients, which can be used as a special environment for research or practical applications in materials processing, life science studies, physical and chemical reactions, etc. To make full use of a superconducting magnet, shared instruments (the operating platform, sample holders, temperature controller, and observation system) must be prepared as prerequisites. This paper introduces the design of a set of sample holders and a temperature controller in detail with an emphasis on validating the performance of the force and temperature sensors in the high-magnetic field.

Experience with overcooling and refilling of large superconducting magnets

Directory of Open Access Journals (Sweden)

Peter Trojan

2008-11-01

Full Text Available Cooling process of big superconducting magnets from temperature of surrounding to the critical temperature is a verycomplicated process from economical as well as from technical view. In case when cryostat containing experimental device overcoolitself from normal temperature directly with liquid helium the consumption would be considerably higher than in case that we use liquidnitrogen for first overcool. Thus whole process of overcooling would be considerably nonprofitable. The article describes experiencewith overflowing of superconducting magnets installed in laboratory at the Technical University in Kosice, where the research projectfor the electric energy in the magnetic field storage takes place.

Hip and upper extremity kinematics in youth baseball pitchers.

Science.gov (United States)

Holt, Taylor; Oliver, Gretchen D

2016-01-01

The purpose of this study was to examine the relationship between dynamic hip rotational range of motion and upper extremity kinematics during baseball pitching. Thirty-one youth baseball pitchers (10.87 ± 0.92 years; 150.03 ± 5.48 cm; 44.83 ± 8.04 kg) participated. A strong correlation was found between stance hip rotation and scapular upward rotation at maximum shoulder external rotation (r = 0.531, P = 0.002) and at ball release (r = 0.536, P = 0.002). No statistically significant correlations were found between dynamic hip rotational range of motion and passive hip range of motion. Hip range of motion deficits can constrain pelvis rotation and limit energy generation in the lower extremities. Shoulder pathomechanics can then develop as greater responsibility is placed on the shoulder to generate the energy lost from the proximal segments, increasing risk of upper extremity injury. Additionally, it appears that passive seated measurements of hip range of motion may not accurately reflect the dynamic range of motion of the hips through the progression of the pitch cycle.

Superconductivity in power engineering

International Nuclear Information System (INIS)

1989-01-01

This proceedings volume presents 24 conference papers and 15 posters dealing with the following aspects: 1) Principles and elementary aspects of high-temperature superconductivity (3 plenary lectures); 2) Preparation, properties and materials requirements of metallic or oxide superconductors (critical current behaviour, soldered joints, structural studies); 3) Magnet technology (large magnets for thermonuclear fusion devices; magnets for particle accelerators and medical devices); 4) Magnetic levitation and superconductivity; 5) Cryogenics; 6) Energy storage systems using superconducting coils (SMES); 7) Superconducting power transmission cables, switches, transformers, and generator systems for power plant; 8) Supporting activities, industrial aspects, patents. There are thirty-eight records in the ENERGY database relating to individual conference papers. (MM) [de

Accelerators and superconductivity: A marriage of convenience

International Nuclear Information System (INIS)

Wilson, M.

1987-01-01

This lecture deals with the relationship between accelerator technology in high-energy-physics laboratories and the development of superconductors. It concentrates on synchrotron magnets, showing how their special requirements have brought about significant advances in the technology, particularly the development of filamentary superconducting composites. Such developments have made large superconducting accelerators an actuality: the Tevatron in routine operation, the Hadron Electron Ring Accelerator (HERA) under construction, and the Superconducting Super Collider (SSC) and Large Hadron Collider (LHC) at the conceptual design stage. Other applications of superconductivity have also been facilitated - for example medical imaging and small accelerators for industrial and medical use. (orig.)

The development of superconducting equipment

CERN Document Server

Ueda, T; Hiue, H

2003-01-01

Fuji Electric has been developing various types of superconducting equipment for over a quarter of a century. This paper describes the development results achieved for superconducting equipment and especially focuses on large-capacity current leads and superconducting transmission systems, the development of which is being promoted for application to the field of nuclear fusion. High temperature superconductor (HTS) is becoming the mainstream in the field of superconductivity, and the HTS floating coil and conduction-cooled HTS transformed are also introduced as recent developments for devices that utilize this technology. (author)

Superconducting magnets in high energy physics

International Nuclear Information System (INIS)

Prodell, A.G.

1978-01-01

The applications of superconducting magnets in high energy physics in the last ten years have made feasible developments which are vital to high energy research. These developments include high magnetic field, large volume detectors, such as bubble chambers, required for effective resolution of high energy particle trajectories, particle beam transport magnets, and superconducting focusing and bending magnets for the very high energy accelerators and storage rings needed to pursue the study of interactions between elementary particles. The acceptance of superconductivity as a proven technology in high energy physics was reinforced by the recognition that the existing large accelerators using copper-iron magnets had reached practical limits in terms of magnetic field intensity, cost, space, and energy usage, and that large-volume, high-field, copper-iron magnets were not economically feasible. Some of the superconducting magnets and associated systems being used in and being developed for high energy physics are described

Cryogenic systems for large superconducting accelerators/storage rings

International Nuclear Information System (INIS)

Brown, D.P.

1981-01-01

Particle accelerators and storage rings which utilize superconducting magnets have presented cryogenic system designers, as well as magnet designers, with many new challenges. When such accelerators were first proposed, little operational experience existed to guide the design. Two superconducting accelerators, complete with cryogenic systems, have been designed and are now under construction. These are the Fermilab Doubler Project and the Brookhaven National Laboratory ISABELLE Project. The cryogenic systems which developed at these two laboratories share many common characteristics, especially as compared to earlier cryogenic systems. Because of this commonality, these characteristics can be reasonably taken as also being representative of future systems. There are other areas in which the two systems are dissimilar. In those areas, it is not possible to state which, if either, will be chosen by future designers. Some of the design parameters for the two systems are given

Superconductivity in bad metals

International Nuclear Information System (INIS)

Emery, V.J.; Kivelson, S.A.

1995-01-01

It is argued that many synthetic metals, including high temperature superconductors are ''bad metals'' with such a poor conductivity that the usual mean-field theory of superconductivity breaks down because of anomalously large classical and quantum fluctuations of the phase of the superconducting order parameter. Some consequences for high temperature superconductors are described

The Economics of the Duration of the Baseball World Series

Science.gov (United States)

Cassuto, Alexander E.; Lowenthal, Franklin

2007-01-01

This note examines some statistical features of the major league baseball World Series. We show that, based upon actual historical data, we cannot reject the hypothesis that the two World Series teams are evenly matched. Yet, we can also calculate the relative strengths of the teams that would best match the actual outcomes, and we find that those…

Superconducting Fullerene Nanowhiskers

Directory of Open Access Journals (Sweden)

Yoshihiko Takano

2012-04-01

Full Text Available We synthesized superconducting fullerene nanowhiskers (C₆₀NWs by potassium (K intercalation. They showed large superconducting volume fractions, as high as 80%. The superconducting transition temperature at 17 K was independent of the K content (x in the range between 1.6 and 6.0 in K-doped C₆₀ nanowhiskers (K_xC₆₀NWs, while the superconducting volume fractions changed with x. The highest shielding fraction of a full shielding volume was observed in the material of K_3.3C₆₀NW by heating at 200 °C. On the other hand, that of a K-doped fullerene (K-C₆₀ crystal was less than 1%. We report the superconducting behaviors of our newly synthesized K_xC₆₀NWs in comparison to those of K_xC₆₀ crystals, which show superconductivity at 19 K in K₃C₆₀. The lattice structures are also discussed, based on the x-ray diffraction (XRD analyses.

Knee Angle and Stride Length in Association with Ball Speed in Youth Baseball Pitchers

Directory of Open Access Journals (Sweden)

Bart van Trigt

2018-05-01

Full Text Available The purpose of this study was to determine whether stride length and knee angle of the leading leg at foot contact, at the instant of maximal external rotation of the shoulder, and at ball release are associated with ball speed in elite youth baseball pitchers. In this study, fifty-two elite youth baseball pitchers (mean age 15.2 SD (standard deviation 1.7 years pitched ten fastballs. Data were collected with three high-speed video cameras at a frequency of 240 Hz. Stride length and knee angle of the leading leg were calculated at foot contact, maximal external rotation, and ball release. The associations between these kinematic variables and ball speed were separately determined using generalized estimating equations. Stride length as percentage of body height and knee angle at foot contact were not significantly associated with ball speed. However, knee angles at maximal external rotation and ball release were significantly associated with ball speed. Ball speed increased by 0.45 m/s (1 mph with an increase in knee extension of 18 degrees at maximal external rotation and 19.5 degrees at ball release. In conclusion, more knee extension of the leading leg at maximal external rotation and ball release is associated with higher ball speeds in elite youth baseball pitchers.

Potential of Partially Superconducting Generators for Large Direct-Drive Wind Turbines

DEFF Research Database (Denmark)

Liu, Dong; Polinder, Henk; Abrahamsen, Asger Bech

2017-01-01

This paper aims at assessing the potential of partially superconducting generators for 10 MW direct-drive wind turbines by investigating their performance for a very wide range of excitation currents. Performance indicators such as shear stress and efficiency and other generator characteristics...... are compared for 12 different generator topologies. To be sufficiently attractive, superconducting generators must have significant advantages over permanent magnet direct-drive generators, which typically have shear stresses of the order of 53 kPa and efficiencies of 96%. Therefore, we investigate what...... they achieve this performance. By examining the maximum magnetic flux density at the location of the superconducting field winding, feasible superconductors can be chosen according to their engineering current density capabilities. It is found that high- and low-temperature superconductors can meet...

Superconductivity

International Nuclear Information System (INIS)

Buller, L.; Carrillo, F.; Dietert, R.; Kotziapashis, A.

1989-01-01

Superconductors are materials which combine the property of zero electric resistance with the capability to exclude any adjacent magnetic field. This leads to many large scale applications such as the much publicized levitating train, generation of magnetic fields in MHD electric generators, and special medical diagnostic equipment. On a smaller-scale, superconductive materials could replace existing resistive connectors and decrease signal delays by reducing the RLC time constants. Thus, a computer could operate at much higher speeds, and consequently at lower power levels which would reduce the need for heat removal and allow closer spacing of circuitry. Although technical advances and proposed applications are constantly being published, it should be recognized that superconductivity is a slowly developing technology. It has taken scientists almost eighty years to learn what they now know about this material and its function. The present paper provides an overview of the historical development of superconductivity and describes some of the potential applications for this new technology as it pertains to the electronics industry

Superconductivity in doped insulators

International Nuclear Information System (INIS)

Emery, V.J.; Kivelson, S.A.

1995-01-01

It is shown that many synthetic metals, including high temperature superconductors are ''bad metals'', with such a poor conductivity that the usual meanfield theory of superconductivity breaks down because of anomalously large classical and quantum fluctuations of the phase of the superconducting order parameter. It is argued that the supression of a first order phase transition (phase separation) by the long-range Coulomb interaction leads to high temperature superconductivity accompanied by static or dynamical charge inhomogeneIty. Evidence in support of this picture for high temperature superconductors is described

Large superconducting conductors and joints for fusion magnets: From conceptual design to test at full size scale

International Nuclear Information System (INIS)

Ciazynski, D.; Duchateau, J.L.; Decool, P.; Libeyre, P.; Turck, B.

2001-01-01

A new kind of superconducting conductor, using the so-called cable-in-conduit concept, is emerging mainly involving fusion activity. It is to be noted that at present time no large Nb 3 Sn magnet in the world is operating using this concept. The difficulty of this technology which has now been studied for 20 years, is that it has to integrate major progresses in multiple interconnected new fields such as: large number (1000) of superconducting strands, high current conductors (50 kA), forced flow cryogenics, Nb 3 Sn technology, low loss conductors in pulsed operation, high current connections, high voltage insulation (10 kV), economical and industrial feasibility. CEA was very involved during these last 10 years in this development which took place in the frame of the NET and ITER technological programs. One major milestone was reached in 1998-1999 with the successful tests by our Association of three full size conductor and connection samples in the Sultan facility (Villigen, Switzerland). (author)

Plasma processing of large curved surfaces for superconducting rf cavity modification

Directory of Open Access Journals (Sweden)

J. Upadhyay

2014-12-01

Full Text Available Plasma-based surface modification of niobium is a promising alternative to wet etching of superconducting radio frequency (SRF cavities. We have demonstrated surface layer removal in an asymmetric nonplanar geometry, using a simple cylindrical cavity. The etching rate is highly correlated with the shape of the inner electrode, radio-frequency (rf circuit elements, gas pressure, rf power, chlorine concentration in the Cl_{2}/Ar gas mixtures, residence time of reactive species, and temperature of the cavity. Using variable radius cylindrical electrodes, large-surface ring-shaped samples, and dc bias in the external circuit, we have measured substantial average etching rates and outlined the possibility of optimizing plasma properties with respect to maximum surface processing effect.

A Study of the Interaction between Batting Cage Baseballs and Pitching Machine

Directory of Open Access Journals (Sweden)

Patrick Drane

2018-02-01

Full Text Available Batting cage pitching machines are widely used across the sports of baseball and softball for training and recreation purposes. The balls are specifically designed for the machines and for the environment to ensure high durability and typically do not have seams. Polymeric foam balls are widely used in these automated pitching machines for batting practice in a cage environment and are similar in weight and size compared with the regulation balls used in leagues. The primary objective of this paper is to characterize the polymeric balls and their interaction with the pitching machine. The paper will present measured ball properties and measured relationships between various pitching machine parameters such as wheel speed, and the ratio of wheel speeds on the ball exit velocity and rotation. This paper will also characterize some of the effects of wear on the baseballs and wheels from their prolonged use.

Reliability of large superconducting magnets through design

International Nuclear Information System (INIS)

Henning, C.D.

1980-01-01

As superconducting magnet systems grow larger and become the central component of major systems involving fusion, magnetohydrodynamics, and high-energy physics, their reliability must be commensurate with the enormous capital investment in the projects. Although the magnet may represent only 15% of the cost of a large system such as the Mirror Fusion Test Facility, its failure would be catastrophic to the entire investment. Effective quality control during construction is one method of ensuring success. However, if the design is unforgiving, even an inordinate amount of effort expended on quality control may be inadequate. Creative design is the most effective way of ensuring magnet reliability and providing a reasonable limit on the amount of quality control needed. For example, by subjecting the last drawing operation is superconductor manufacture to a stress larger than the magnet design stress, a 100% proof test is achieved; cabled conductors offer mechanical redundancy, as do some methods of conductor joining; ground-plane insulation should be multilayered to prevent arcs, and interturn and interlayer insulation spaced to be compatible with the self-extinguishing of arcs during quench voltages; electrical leads should be thermally protected; and guard vacuum spaces can be incorporated to control helium leaks. Many reliable design options are known to magnet designers. These options need to be documented and organized to produce a design guide. Eventually, standard procedures, safety factors, and design codes can lead to reliability in magnets comparable to that obtained in pressure vessels and other structures. Wihout such reliability, large-scale applications in major systems employing magnetic fusion energy, magnetohydrodynamics, or high-energy physics would present unacceptable economic risks

Computing and data handling requirements for SSC [Superconducting Super Collider] and LHC [Large Hadron Collider] experiments

International Nuclear Information System (INIS)

Lankford, A.J.

1990-05-01

A number of issues for computing and data handling in the online in environment at future high-luminosity, high-energy colliders, such as the Superconducting Super Collider (SSC) and Large Hadron Collider (LHC), are outlined. Requirements for trigger processing, data acquisition, and online processing are discussed. Some aspects of possible solutions are sketched. 6 refs., 3 figs

Applied superconductivity and cryogenic research activities in NIFS

International Nuclear Information System (INIS)

Mito, T.; Sagara, A.; Imagawa, S.; Yamada, S.; Takahata, K.; Yanagi, N.; Chikaraishi, H.; Maekawa, R.; Iwamoto, A.; Hamaguchi, S.; Sato, M.; Noda, N.; Yamauchi, K.; Komori, A.; Motojima, O.

2006-01-01

Since the foundation of National Institute for Fusion Science (NIFS) in 1989, the primary mission of the applied superconductivity and cryogenic researches has been focused on the development of the large helical device (LHD): the largest fusion experimental apparatus exclusively utilizing superconducting technologies. The applied superconductivity and cryogenics group in NIFS was organized to be responsible for this activity. As a result of extensive research activities, the construction of LHD was completed in 1997. Since then, the LHD superconducting system has been demonstrating high availability of more than 97% during eight years operation and it keeps proving high reliability of large-scale superconducting systems. This paper describes the extensive activities of the applied superconductivity and cryogenic researches in NIFS during and after the development of LHD and the fundamental researches that aim at realizing a helical-type fusion reactor

Superconducting cyclotrons

International Nuclear Information System (INIS)

Blosser, H.G.; Johnson, D.A.; Burleigh, R.J.

1976-01-01

Superconducting cyclotrons are particularly appropriate for acceleration of heavy ions. A review is given of design features of a superconducting cyclotron with energy 440 (Q 2 /A) MeV. A strong magnetic field (4.6 tesla average) leads to small physical size (extraction radius 65 cm) and low construction costs. Operating costs are also low. The design is based on established technology (from present cyclotrons and from large bubble chambers). Two laboratories (in Chalk River, Canada and in East Lansing, Michigan) are proceeding with construction of full-scale prototype components for such cyclotrons

Magnesium Diboride Superconducting Coils for Electric Propulsion Systems for Large Aircraft, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — The recent development of magnesium diboride superconducting wires makes possible the potential to have much lighter weight superconducting coils for heavy aircraft...

Superconducting pipes and levitating magnets.

Science.gov (United States)

Levin, Yan; Rizzato, Felipe B

2006-12-01

Motivated by a beautiful demonstration of the Faraday and the Lenz laws in which a small neodymium magnet falls slowly through a conducting nonferromagnetic tube, we consider the dynamics of a magnet falling coaxially through a superconducting pipe. Unlike the case of normal conducting pipes, in which the magnet quickly reaches the terminal velocity, inside a superconducting tube the magnet falls freely. On the other hand, to enter the pipe the magnet must overcome a large electromagnetic energy barrier. For sufficiently strong magnets, the barrier is so large that the magnet will not be able to penetrate it and will be levitated over the mouth of the pipe. We calculate the work that must done to force the magnet to enter a superconducting tube. The calculations show that superconducting pipes are very efficient at screening magnetic fields. For example, the magnetic field of a dipole at the center of a short pipe of radius a and length L approximately > a decays, in the axial direction, with a characteristic length xi approximately 0.26a. The efficient screening of the magnetic field might be useful for shielding highly sensitive superconducting quantum interference devices. Finally, the motion of the magnet through a superconducting pipe is compared and contrasted to the flow of ions through a trans-membrane channel.

Bilateral differences in the upper quarter function of high school aged baseball and softball players.

Science.gov (United States)

Butler, Robert J; Myers, Heather S; Black, Douglass; Kiesel, Kyle B; Plisky, Phillip J; Moorman, Claude T; Queen, Robin M

2014-08-01

The Upper Quarter Y Balance Test (YBT-UQ) was developed as a way to identify upper extremity and trunk mobility in the open kinetic chain in the reaching limb as well as midrange limitations and asymmetries of upper extremity and core stability in the closed kinetic chain on the stabilizing limb. Performance on the YBT-UQ is similar between genders and between limbs; however, this has not been examined in athletes who participate in sports that result in upper extremity asymmetries. The primary purpose of this study is to determine if differences exist between the throwing vs. non-throwing sides in high-school baseball and softball athletes on the YBT-UQ. In order to complete this forty-eight male high school baseball players and seventeen female high school softball players were tested on the YBT-UQ. Reach distances were normalized to arm length (% AL). Comparisons were made between the throwing (T) and non-throwing (NT) arm for each direction as well as the composite score. No significant differences were observed between the T and NT arm for the medial (NT: 98.4 ± 8.6 %AL, T: 99.1 ± 8.6 %AL, p=0.42), inferolateral (NT: 90.8 ± 11.8 %AL, T: 90.3 ± 11.5 %AL, p =0.61), superolateral (NT: 70.6 ± 10.9 %AL, T: 70.4 ± 11.1 % AL, p=0.91) reaches, or the composite score (NT: 87.2 ± 8.9 % AL, T: 86.6 ± 8.1 %AL, p=0.72). Similarly, no differences were observed between the male baseball and female softball players (p=0.30-0.90). Based on these findings, it was concluded that there was no difference in performance on the YBT-UQ between throwing and non-throwing limbs in high school baseball and softball players. 3.

As Cutbacks Hit College Sports, Baseball Falls behind in the Count

Science.gov (United States)

Wolverton, Brad

2009-01-01

For two weeks every June, the College World Series showcases one of the National Collegiate Athletic Association's (NCAA's) most popular sports. More than 300,000 fans flock to picturesque Rosenblatt Stadium, in Omaha, with millions more tuning in on ESPN. Ticket sales, which in recent years topped $9-million, make baseball the NCAA's…

Three-terminal superconducting devices

International Nuclear Information System (INIS)

Gallagher, W.J.

1985-01-01

The transistor has a number of properties that make it so useful. The authors discuss these and the additional properties a transistor would need to have for high performance applications at temperatures where superconductivity could contribute advantages to system-level performance. These properties then serve as criteria by which to evaluate three-terminal devices that have been proposed for applications at superconducting temperatures. FETs can retain their transistor properties at low temperatures, but their power consumption is too large for high-speed, high-density cryogenic applications. They discuss in detail why demonstrated superconducting devices with three terminals -Josephson effect based devices, injection controlled weak links, and stacked tunnel junction devices such as the superconducting transistor proposed by K. Gray and the quiteron -- each fail to have true transistor-like properties. They conclude that the potentially very rewarding search for a transistor compatible with superconductivity in high performance applications must be in new directions

The present role of superconductivity in fusion

International Nuclear Information System (INIS)

Shimamoto, S.

1986-01-01

After completion of large fusion devices in the world, such as JT-60, JET and TFTR, high temperature plasma is proceeding to critical condition for fusion. The devices up to now use mainly conventional magnet. However, for the next generation machine which demonstrates fusion reaction, deuterium-tritium burning, superconducting magnet system is indispensable from view point of both net energy extraction and capacity limitation of power supply. In order to realize such a large and complicated system, a lot of development works is being carried out. This paper describes required parameters of superconducting magnet and helium refrigerator, the state of plasma condition and superconducting magnet. It is shown that the present technology of superconducting magnet is not so far from realization of fusion experimental reactor

A Highly Miniaturized, Wireless Inertial Measurement Unit for Characterizing the Dynamics of Pitched Baseballs and Softballs

Science.gov (United States)

McGinnis, Ryan S.; Perkins, Noel C.

2012-01-01

Baseball and softball pitch types are distinguished by the path and speed of the ball which, in turn, are determined by the angular velocity of the ball and the velocity of the ball center at the instant of release from the pitcher's hand. While radar guns and video-based motion capture (mocap) resolve ball speed, they provide little information about how the angular velocity of the ball and the velocity of the ball center develop and change during the throwing motion. Moreover, mocap requires measurements in a controlled lab environment and by a skilled technician. This study addresses these shortcomings by introducing a highly miniaturized, wireless inertial measurement unit (IMU) that is embedded in both baseballs and softballs. The resulting “ball-embedded” sensor resolves ball dynamics right on the field of play. Experimental results from ten pitches, five thrown by one softball pitcher and five by one baseball pitcher, demonstrate that this sensor technology can deduce the magnitude and direction of the ball's velocity at release to within 4.6% of measurements made using standard mocap. Moreover, the IMU directly measures the angular velocity of the ball, which further enables the analysis of different pitch types.

Development of superconducting wind turbine generators

DEFF Research Database (Denmark)

Jensen, Bogi Bech; Mijatovic, Nenad; Abrahamsen, Asger Bech

2013-01-01

In this paper, the commercial activities in the field of superconducting machines, particularly superconducting wind turbine generators, are reviewed and presented. Superconducting generators have the potential to provide a compact and light weight drive train at high torques and slow rotational...... speeds, because high magnetic fields can be produced by coils with very little loss. Three different superconducting wind turbine generator topologies have been proposed by three different companies. One is based on low temperature superconductors; one is based on high temperature superconductors......; and one is a fully superconducting generator based on MgB2. It is concluded that there is large commercial interest in superconducting machines, with an increasing patenting activity. Such generators are, however, not without their challenges. The superconductors have to be cooled down to somewhere...

Development of Superconducting Wind Turbine Generators

DEFF Research Database (Denmark)

Jensen, Bogi Bech; Mijatovic, Nenad; Abrahamsen, Asger Bech

2012-01-01

In this paper the commercial activities in the field of superconducting machines, particularly superconducting wind turbine generators, are reviewed and presented. Superconducting generators have the potential to provide a compact and light weight drive train at high torques and slow rotational...... speeds, because high magnetic fields can be produced by coils with very little loss. Three different superconducting wind turbine generator topologies have been proposed by three different companies. One is based on low temperature superconductors (LTS); one is based on high temperature superconductors...... (HTS); and one is a fully superconducting generator based on MgB2. It is concluded that there is large commercial interest in superconducting machines, with an increasing patenting activity. Such generators are however not without their challenges. The superconductors have to be cooled down...

Progress on large superconducting toroidal field coils

International Nuclear Information System (INIS)

Haubenreich, P.N.; Luton, J.N.; Thompson, P.B.; Beard, D.S.

1979-01-01

Large superconducting toroidal field coils of competing designs are being produced by six major industrial teams. In the US, teams headed by General Dynamics Convair, General Electric, and Westinghouse are under contract to design and fabricate one coil each to specifications established by the Large Coil Program. A facility for testing 6 coils in a toroidal array at fields to 8 to 12 tesla is under construction at Oak Ridge. Through an international agreement, EURATOM, Japan, and Switzerland will produce one coil each for testing with the US coils. Each test coil will have a 2.5 x 3.5 m D-shape winding bore and is designed to operate at a current of 10 to 18 kA at a peak field of 8T while subjected to pulsed fields of 0.14 T applied in 1.0 s. There are significant differences among the six coil designs: five use NbTi, one Nb 3 Sn; three are cooled by pool boiling helium, three by forced flow; five have welded or bolted stainless steel coil cases, one has aluminum plate structure. All are designed to be cryostable at 8T, with structural margin for extended operation. The three US coil teams are almost or completely finished with detailed design and are now procuring materials and setting up manufacturing equipment. The non-US teams are at various stages of verification testing and design. The GDC and GE coils are scheduled for delivery in the spring of 1981 and the others will be completed a year later. The 11-m diameter vessel at the test facility has been completed and major components of the test stand are being procured. Engineering and procurement to upgrade the helium liquifier-refrigerator system are under way

A Model of Motor Inhibition for a Complex Skill: Baseball Batting

Science.gov (United States)

Gray, Rob

2009-01-01

The ability to inhibit an ongoing action in response to a signal from the environment is important for many perceptual-motor actions. This paper examines a particular example of this behavior: attempting to inhibit or "check" a swing in baseball batting. A model of motor inhibition in batting is proposed. In the model there are three different…

A study of static, kinetic, and dynamic visual acuity in 102 Japanese professional baseball players

Directory of Open Access Journals (Sweden)

Hoshina K

2013-03-01

Full Text Available Kohji Hoshina,1 Yuichi Tagami,2 Osamu Mimura,3 Hiroshi Edagawa,4 Masao Matsubara,5 Teiichi Nakayama6 1Hoshina Eye Clinic, Nishinomiya, Japan; 2Department of Ophthalmology, Kobe Century Memorial Hospital, Kobe, Japan; 3Department of Ophthalmology, Hyogo College of Medicine, Nishinomiya, Japan; 4Edagawa Eye Clinic, Tokyo, Japan; 5Department of Ophthalmology, Tokyo Women's Medical University Medical Center East, Tokyo, Japan; 6Ritsumeikan University, Kyoto, Japan Background: It seemed that visual functions might have some effects on the performance of baseball players. We measured static, kinetic, and dynamic visual acuity (SVA, KVA, and DVA, respectively of Japanese professional baseball players to ascertain whether there would be any difference in SVA, KVA, and DVA among player groups stratified according to their performance level. Methods: The subjects were 102 male professional baseball players with a mean age of 26 years who were members of a Japanese professional baseball club from 2000 to 2009. They were stratified into three groups according to their performance level: A (players who were on the roster of the top-level team all the time throughout the study period, B (players who were on the roster of the top-level team sometimes but not all the time, and C (players who were never on the roster of the top-level team. They were interviewed for the use of corrective visual aids, and examined for SVA, KVA, and DVA. The measurements of these parameters were compared among groups A, B, and C. We also investigated and analyzed the association of KVA or DVA with player position (pitchers or fielders and with hand dominance for batting. KVA was compared between the pitchers and the fielders because they each require different playing skills. DVA was compared between the right-handed and the left-handed batters. Results: There was no statistically significant difference among groups A, B, and C. There was a statistically significant difference in

Power flow control and damping enhancement of a large wind farm using a superconducting magnetic energy storage unit

DEFF Research Database (Denmark)

Chen, S. S.; Wang, L.; Lee, W. J.

2009-01-01

A novel scheme using a superconducting magnetic energy storage (SMES) unit to perform both power flow control and damping enhancement of a large wind farm (WF) feeding to a utility grid is presented. The studied WF consisting of forty 2 MW wind induction generators (IGs) is simulated...

Design considerations for a large aperture high field superconducting dipole

International Nuclear Information System (INIS)

Harfoush, F.; Ankenbrandt, C.; Harrison, M.; Kerby, J.; Koepke, K.; Mantsch, P.; Nicol, T.; Riddiford, A.; Theilacker, J.

1989-03-01

The final phase of the Fermilab upgrade proposal calls for a new ring of superconducting magnets to be placed in the existing Main Accelerator tunnel. The goal of this design study is to specify a high field dipole (HFD) that is capable of supporting fixed target operation (ramping, resonant extraction) at a field of 6.6T (1.5 Tev) and colliding beam physics at 8.0T (1.8 Tev). The magnetic field quality at high field is set by the large amplitude orbits associated with resonant extraction. The field quality must therefore be at least as good as the existing Tevatron magnets which fulfill these criteria. The high fields and large aperture of this magnet result in large forces on the coil and collar assemblies. Therefore, the cold mass design must be able to sustain these forces while providing sufficient cooling to the coils during 4.2 K fixed target operation, and a minimum heat load during 1.8 K collider operation. The design work is still in progress but a cosine-theta, cold-iron dipole with a 70mm inner diameter coil has been tentatively adopted. This report presents details on the conductor and cable parameters, coil cross-section, projected manufacturing tolerances, iron yoke design, and cold mass assembly. 4 refs., 5 figs., 1 tab

Design considerations for a large aperture high field superconducting dipole

Energy Technology Data Exchange (ETDEWEB)

Harfoush, F.; Ankenbrandt, C.; Harrison, M.; Kerby, J.; Koepke, K.; Mantsch, P.; Nicol, T.; Riddiford, A.; Theilacker, J.

1989-03-01

The final phase of the Fermilab upgrade proposal calls for a new ring of superconducting magnets to be placed in the existing Main Accelerator tunnel. The goal of this design study is to specify a high field dipole (HFD) that is capable of supporting fixed target operation (ramping, resonant extraction) at a field of 6.6T (1.5 Tev) and colliding beam physics at 8.0T (1.8 Tev). The magnetic field quality at high field is set by the large amplitude orbits associated with resonant extraction. The field quality must therefore be at least as good as the existing Tevatron magnets which fulfill these criteria. The high fields and large aperture of this magnet result in large forces on the coil and collar assemblies. Therefore, the cold mass design must be able to sustain these forces while providing sufficient cooling to the coils during 4.2 K fixed target operation, and a minimum heat load during 1.8 K collider operation. The design work is still in progress but a cosine-theta, cold-iron dipole with a 70mm inner diameter coil has been tentatively adopted. This report presents details on the conductor and cable parameters, coil cross-section, projected manufacturing tolerances, iron yoke design, and cold mass assembly. 4 refs., 5 figs., 1 tab.

Superconductivity: Its Role, Its Success and Its Setbacks in the Large Hadron Collider of CERN

CERN Document Server

Rossi, L

2010-01-01

The Large Hadron Collider - LHC, the particle accelerator at CERN, Geneva, is the largest and probably the most complex scientific instrument ever built. Superconductivity plays a key role because the accelerator is based on the reliable operation of almost 10,000 superconducting magnets cooled by 130 tonnes of helium at 1.9 and 4.2 K and containing a total stored magnetic energy of about 15,000 MJ (including detector magnets). The characteristics of the 1200 tonnes of high quality Nb-Ti cables have met the severe requests in terms of critical currents, magnetization and inter-strand resistance; the magnets are built with an unprecedented uniformity, about 0.01% of variation in field quality among the 1232 main dipoles which are 15 m in length and 30 tonnes in weight. The results of this 20 year long enterprise will be discussed together with problems faced during construction and commissioning and their remedies. Particular reference is made to the severe incident which occurred nine days after the spectacul...

Investigation of transient electrical, magnetic, and mechanical phenomena in large superconducting magnet coils

International Nuclear Information System (INIS)

Sihler, C.

1996-07-01

The progress in the field of technology for superconducting magnets led to the necessity of transferring existing calculation methods from electrical power engineering, modifying these tools to satisfy the boundary conditions for superconducting magnets, and also developing new calculation methods for special purposes. In this work suitable calculation methods are elaborated. Their validity and applicability is demonstrated in employing these scientific engineering tools to actual developments of the Forschungszentrum Karlsruhe. In detail this work deals with: 1. calculating eddy current and force densities in the conducting environment of a superconducting magnet or magnet system. 2. the effects of eddy current forces in experimental engineering; 3. transient effects of electrical surges acting on new coil designs; and 4. the electrical and magnetic properties of superconducting cables. Especially, the magnetic properties can lead to an inhomogeneous current distribution in the cable and, thus, to a considerable reduction of the current carrying capacity of the whole magnet. These investigations demonstrate that a detailed analysis of electrodynamic phenomena is indispensable in order to find the optimum technical way to make use of the physical potential of superconductivity. (orig./MM) [de

Internal- and External-Rotation Peak Toque in Little League Baseball Players With Subacromial Impingement Syndrome: Improved by Closed Kinetic Chain Shoulder Training.

Science.gov (United States)

Lee, Dong-Rour; Kim, Laurentius Jongsoon

2016-08-01

Many studies have explored closed kinetic chain (CKC) shoulder exercises (SEs) with a sling because they are safer and more effective than open-chain exercises, especially in early stages of treatment. However, the application of CKC SE in youth baseball players has rarely been attempted, although teenage baseball players also experience shoulder pain. To investigate the effects of CKC SE on the peak torque of shoulder internal rotation (IR) and external rotation (ER) in youth baseball players. Single-group pretest, posttest. Biomechanics laboratory. 23 Little League Baseball players with subacromial impingement syndrome. The CKC SE with a sling was CKC shoulder-flexion exercise, extension exercise, IR exercise, and ER exercise. This exercise regimen was conducted 2 or 3 times/wk for 8 wk. The peak torque of shoulder IR and ER was measured using an isokinetic dynamometer. Concentric shoulder rotation was performed, with 5 repetitions at an angular velocity of 60°/s and 15 at 180°/s. The IR and ER peak torque significantly increased at each angular velocity after the exercise program. In particular, the increase in IR and ER peak torque values was statistically significant at an angular velocity of 180°/s. CKC SE was effective in increasing shoulder IR and ER strength, demonstrating its potential benefits in the prevention and treatment of shoulder injury. In addition, increased IR peak torque appears to improve throwing velocity in baseball players.

Superconducting cavities for beauty factories

International Nuclear Information System (INIS)

Lengeler, H.

1992-01-01

The possibilities and merits of superconducting accelerating cavities for Beauty-factories are considered. There exist already large sc systems of size and frequency comparable to the ones needed for Beauty-factories. Their status and operation experience is discussed. A comparison of normal conducting and superconducting systems is done for two typical Beauty-factory rings

Osteochondritis Dissecans of the Glenoid in a Major League Baseball Prospect: A Case Report.

Science.gov (United States)

Grau, Luis Carlos; Jose, Jean; Sama, Andrew Joseph; Baraga, Michael Gerald

2016-01-01

A 16-year-old Major League Baseball prospect presented with persistent shoulder pain associated with throwing. Magnetic resonance imaging (MRI) demonstrated a large osteochondritis dissecans lesion in the posterosuperior aspect of the glenoid. The patient was restricted from throwing and underwent therapy to improve range of motion and throwing mechanics. Eight months after initiating nonoperative treatment, an MRI arthrogram demonstrated a healed lesion. At follow-up 2 years after treatment, full relief of symptoms had persisted. Osteochondritis dissecans lesions of the glenoid are extremely rare, but have the potential to heal in overhead-throwing athletes. To our knowledge, this is the only case reported in the literature that demonstrates a healed osteochondritis dissecans lesion of the glenoid following nonoperative treatment.

Superconducting nanostructured materials

International Nuclear Information System (INIS)

Metlushko, V.

1998-01-01

Within the last year it has been realized that the remarkable properties of superconducting thin films containing a periodic array of defects (such as sub-micron sized holes) offer a new route for developing a novel superconducting materials based on precise control of microstructure by modern photolithography. A superconductor is a material which, when cooled below a certain temperature, loses all resistance to electricity. This means that superconducting materials can carry large electrical currents without any energy loss--but there are limits to how much current can flow before superconductivity is destroyed. The current at which superconductivity breaks down is called the critical current. The value of the critical current is determined by the balance of Lorentz forces and pinning forces acting on the flux lines in the superconductor. Lorentz forces proportional to the current flow tend to drive the flux lines into motion, which dissipates energy and destroys zero resistance. Pinning forces created by isolated defects in the microstructure oppose flux line motion and increase the critical current. Many kinds of artificial pinning centers have been proposed and developed to increase critical current performance, ranging from dispersal of small non-superconducting second phases to creation of defects by proton, neutron or heavy ion irradiation. In all of these methods, the pinning centers are randomly distributed over the superconducting material, causing them to operate well below their maximum efficiency. We are overcome this drawback by creating pinning centers in aperiodic lattice (see Fig 1) so that each pin site interacts strongly with only one or a few flux lines

The effect of repetitive baseball pitching on medial elbow joint space gapping associated with 2 elbow valgus stressors in high school baseball players.

Science.gov (United States)

Hattori, Hiroshi; Akasaka, Kiyokazu; Otsudo, Takahiro; Hall, Toby; Amemiya, Katsuya; Mori, Yoshihisa

2018-04-01

To prevent elbow injury in baseball players, various methods have been used to measure medial elbow joint stability with valgus stress. However, no studies have investigated higher levels of elbow valgus stress. This study investigated medial elbow joint space gapping measured ultrasonically resulting from a 30 N valgus stress vs. gravitational valgus stress after a repetitive throwing task. The study included 25 high school baseball players. Each subject pitched 100 times. The ulnohumeral joint space was measured ultrasonographically, before pitching and after each successive block of 20 pitches, with gravity stress or 30 N valgus stress. Two-way repeated measures analysis of variance and Pearson correlation coefficient analysis were used. The 30 N valgus stress produced significantly greater ulnohumeral joint space gapping than gravity stress before pitching and at each successive 20-pitch block (P space gapping increased significantly from baseline after 60 pitches (P space gapping (r = 0.727-0.859, P space gapping before pitching; however, 30 N valgus stress appears to induce greater mechanical stress, which may be preferable when assessing joint instability but also has the potential to be more aggressive. The present results may indicate that constraining factors to medial elbow joint valgus stress matched typical viscoelastic properties of cyclic creep. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

ASC 84: applied superconductivity conference. Final program and abstracts

International Nuclear Information System (INIS)

1984-01-01

Abstracts are given of presentations covering: superconducting device fabrication; applications of rf superconductivity; conductor stability and losses; detectors and signal processing; fusion magnets; A15 and Nb-Ti conductors; stability, losses, and various conductors; SQUID applications; new applications of superconductivity; advanced conductor materials; high energy physics applications of superconductivity; electronic materials and characterization; general superconducting electronics; ac machinery and new applications; digital devices; fusion and other large scale applications; in-situ and powder process conductors; ac applications; synthesis, properties, and characterization of conductors; superconducting microelectronics

ASC 84: applied superconductivity conference. Final program and abstracts

Energy Technology Data Exchange (ETDEWEB)

1984-01-01

Abstracts are given of presentations covering: superconducting device fabrication; applications of rf superconductivity; conductor stability and losses; detectors and signal processing; fusion magnets; A15 and Nb-Ti conductors; stability, losses, and various conductors; SQUID applications; new applications of superconductivity; advanced conductor materials; high energy physics applications of superconductivity; electronic materials and characterization; general superconducting electronics; ac machinery and new applications; digital devices; fusion and other large scale applications; in-situ and powder process conductors; ac applications; synthesis, properties, and characterization of conductors; superconducting microelectronics. (LEW)

PREFACE: PASREG 2003: International Workshop on Processing and Applications of Superconducting (RE)BCO Large Grain Materials

Science.gov (United States)

Murakami, Masato; Cardwell, David; Salama, Kamel; Krabbes, Gernot; Habisreuther, Tobias; Gawalek, Wolfgang

2005-02-01

Superconducting melt-textured bulk (RE)BCO large grain materials are one of the most promising materials for power applications of high temperature superconductivity at the liquid nitrogen temperature range. Industrial applications are expected in high-speed low-loss magnetic bearings for flywheel energy storage devices, high-dynamic high-torque electric reluctance motors, and MAGLEV transportation systems. The material has high magnetic field trapping capability and therefore a new class of high-field superconducting permanent magnets will soon appear. However, there is still the need to improve the magnetic and mechanical material properties, as well as to increase the single domain size. This special issue contains papers concerning these topics presented at the International Workshop on the Processing and Applications of Superconducting (RE)BCO Large Grain Materials. The workshop was held on the 30 June-2 July 2003 in Jena, Germany, and was organized by the Institut fuer Physikalische Hochtechnologie, Jena. It was the fourth in the series of PASREG workshops after Cambridge, UK (1997), Morioka, Japan (1999), and Seattle, USA (2001). Sixty two contributions were presented at the workshop, 38 oral presentations and 24 poster presentations. This special issue contains 42 papers. The editors are grateful for the support of many colleagues who reviewed the manuscripts to guarantee their high technical quality. The editors also wish to thank Doris Litzkendorf and Tobias Habisreuther from Institut fuer Physikalische Hochtechnologie, Jena, for their assistance with the organization and handling of the manuscripts. Many thanks to the workshop co-chairman Gernot Krabbes from Leibniz-Institut fuer Festkoerper und Werkstoffforschung, Dresden, for hosting the workshop participants in Dresden. Finally, all attendees wish to acknowledge the efforts of Wolfgang Gawalek, Tobias Habisreuther, Doris Litzkendorf and the Team of Department Magnetics from the Institut fuer

Universal transport characteristics of multiple topological superconducting wires with large charging energy

Energy Technology Data Exchange (ETDEWEB)

Kashuba, Oleksiy; Trauzettel, Bjoern [Institut fuer Theoretische Physik und Astrophysik, Universitaet Wuerzburg, 97074 Wuerzburg (Germany); Timm, Carsten [Institut fuer Theoretische Physik, TU Dresden, 01062 Dresden (Germany)

2016-07-01

The system with multiple Majorana states coupled to the normal lead can potentially support the interaction between Majorana fermions and electrons. Such system can be implemented by several floating topological superconducting wires with large charging energy asymmetrically coupled to two normal leads. The analysis of the renormalization flow shows that there is a single fixed point - the strong coupling limit of isotropic antiferromagnetic Kondo model. The topological Kondo-like interaction leads also to the selective renormalization of the tunneling coefficients, strongly enhancing one component and suppressing others. Thus, charging energy crucially changes the transport properties of the system leading to the universal single-channel conductance independently from the values of the initial leads-wires coupling.

Safety and protection for large scale superconducting magnets. FY 1984 report

International Nuclear Information System (INIS)

Thome, R.J.; Pillsbury, R.D. Jr.; Minervini, J.V.

1984-11-01

The Fusion Program is moving rapidly into design and construction of systems using magnets with stored energies in the range of hundreds of megajoules to gigajoules. For example, the toroidal field coil system alone for TFCX would store about 4 GJ and the mirror system MFTF-B would store about 1.6 GJ. Safety and protection analyses of the magnet subsystems become progressively more important as the size and complexity of the installations increase. MIT has been carrying out a program for INEL oriented toward safety and protection in large scale superconducting magnet systems. The program involves collection and analysis of information on actual magnet failures, analyses of general problems associated with safety and protection, and performance of safety oriented experiments. This report summarizes work performed in FY 1984

Pitching Emotions: The Interpersonal Effects of Emotions in Professional Baseball.

Science.gov (United States)

Cheshin, Arik; Heerdink, Marc W; Kossakowski, Jolanda J; Van Kleef, Gerben A

2016-01-01

Sports games are inherently emotional situations, but surprisingly little is known about the social consequences of these emotions. We examined the interpersonal effects of emotional expressions in professional baseball. Specifically, we investigated whether pitchers' facial displays influence how pitches are assessed and responded to. Using footage from the Major League Baseball World Series finals, we isolated incidents where the pitcher's face was visible before a pitch. A pre-study indicated that participants consistently perceived anger, happiness, and worry in pitchers' facial displays. An independent sample then predicted pitch characteristics and batter responses based on the same perceived emotional displays. Participants expected pitchers perceived as happy to throw more accurate balls, pitchers perceived as angry to throw faster and more difficult balls, and pitchers perceived as worried to throw slower and less accurate balls. Batters were expected to approach (swing) when faced with a pitcher perceived as happy and to avoid (no swing) when faced with a pitcher perceived as worried. Whereas previous research focused on using emotional expressions as information regarding past and current situations, our work suggests that people also use perceived emotional expressions to predict future behavior. Our results attest to the impact perceived emotional expressions can have on professional sports.

Recent advances in fullerene superconductivity

CERN Document Server

Margadonna, S

2002-01-01

Superconducting transition temperatures in bulk chemically intercalated fulleride salts reach 33 K at ambient pressure and in hole-doped C sub 6 sub 0 derivatives in field-effect-transistor (FET) configurations, they reach 117 K. These advances pose important challenges for our understanding of high-temperature superconductivity in these highly correlated organic metals. Here we review the structures and properties of intercalated fullerides, paying particular attention to the correlation between superconductivity and interfullerene separation, orientational order/disorder, valence state, orbital degeneracy, low-symmetry distortions, and metal-C sub 6 sub 0 interactions. The metal-insulator transition at large interfullerene separations is discussed in detail. An overview is also given of the exploding field of gate-induced superconductivity of fullerenes in FET electronic devices.

Interplay of magnetism and superconductivity

International Nuclear Information System (INIS)

Akhavan, M.

2006-01-01

After about two decades of intense research since the discovery of high-temperature superconductivity (HTSC) in cuprates, although many aspects of the physics and chemistry of these cuprate superconductors are now well understood, the underlying pairing mechanism remains elusive. Magnetism and superconductivity are usually thought as incompatible, but in number of special materials including HTSCs these two mutually excluding mechanisms are found to coexist. The presence in a system of superconductivity and magnetism, gives rise to a large number of interesting phenomenon. This article provides perspective on recent developments and their implications for our understanding of the interplay between magnetism and superconductivity in new materials. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (Abstract Copyright [2006], Wiley Periodicals, Inc.)

Superconductivity

International Nuclear Information System (INIS)

Palmieri, V.

1990-01-01

This paper reports on superconductivity the absence of electrical resistance has always fascinated the mind of researchers with a promise of applications unachievable by conventional technologies. Since its discovery superconductivity has been posing many questions and challenges to solid state physics, quantum mechanics, chemistry and material science. Simulations arrived to superconductivity from particle physics, astrophysic, electronics, electrical engineering and so on. In seventy-five years the original promises of superconductivity were going to become reality: a microscopical theory gave to superconductivity the cloth of the science and the level of technological advances was getting higher and higher. High field superconducting magnets became commercially available, superconducting electronic devices were invented, high field accelerating gradients were obtained in superconductive cavities and superconducting particle detectors were under study. Other improvements came in a quiet progression when a tornado brought a revolution in the field: new materials had been discovered and superconductivity, from being a phenomenon relegated to the liquid Helium temperatures, became achievable over the liquid Nitrogen temperature. All the physics and the technological implications under superconductivity have to be considered ab initio

Computer simulations of quench properties of thin, large superconducting solenoid magnets

International Nuclear Information System (INIS)

Kishimoto, Takeshi; Mori, Shigeki; Noguchi, Masaharu

1983-01-01

Measured quench data of a 1 m diameter x 1 m thin superconducting solenoid magnet with a single layer aluminum-stabilized NbTi/Cu superconductor of 269 turns were fitted by computer simulations using the one-dimensional approximation. Parameters obtained were used to study quench properties of a 3 m diameter x 5 m (1.5 Tesla) thin superconducting solenoid magnet with a stored magnetic energy of 30 x 10 6 J. Conductor dimensions with which the solenoid could be built substantially safe for the full field quench were optimized. (author)

A Highly Miniaturized, Wireless Inertial Measurement Unit for Characterizing the Dynamics of Pitched Baseballs and Softballs

Directory of Open Access Journals (Sweden)

Noel C. Perkins

2012-08-01

Full Text Available Baseball and softball pitch types are distinguished by the path and speed of the ball which, in turn, are determined by the angular velocity of the ball and the velocity of the ball center at the instant of release from the pitcher’s hand. While radar guns and video-based motion capture (mocap resolve ball speed, they provide little information about how the angular velocity of the ball and the velocity of the ball center develop and change during the throwing motion. Moreover, mocap requires measurements in a controlled lab environment and by a skilled technician. This study addresses these shortcomings by introducing a highly miniaturized, wireless inertial measurement unit (IMU that is embedded in both baseballs and softballs. The resulting “ball-embedded” sensor resolves ball dynamics right on the field of play. Experimental results from ten pitches, five thrown by one softball pitcher and five by one baseball pitcher, demonstrate that this sensor technology can deduce the magnitude and direction of the ball’s velocity at release to within 4.6% of measurements made using standard mocap. Moreover, the IMU directly measures the angular velocity of the ball, which further enables the analysis of different pitch types.

Last LEP superconducting module travels to surface

CERN Multimedia

Patrice Loïez

2001-01-01

The last superconducting module is raised from the Large Electron-Positron (LEP) collider tunnel, through the main shaft, to the surface. Superconducting modules were only used in the LEP-2 phase of the accelerator, from 1996 to 2000.

Development of superconducting equipment for fusion device

International Nuclear Information System (INIS)

Konno, Masayuki; Ueda, Toshio; Hiue, Hisaaki; Ohgushi, Kouzou

1993-01-01

At Fuji Electric Co., Ltd., the development of superconductivity was started from 1960, and superconducting equipment for fusion device has been developed for ten years. The superconducting equipment, which is developed for fusion by Fuji Electric Co., Ltd., are able to be grouped in three categories which are current lead, superconducting coil and superconducting bus-line. The current lead is an electrical feeder between a superconducting coil and an electrical power supply. The rated current of developed current lead is 30kA at continuous use and 100kA at short time use respectively. The advanced disk type coil is developed for the toroidal field coil and some coils are developed for critical current measurement. Superconductor is applied to the superconducting bus-line between the superconducting coils and the current leads, and the bus-line is being developed for the Large Helical Device. This report describes an abstract of these equipment. (author)

Characterization of etch pits found on a large-grain bulk niobium superconducting radio-frequency resonant cavity

OpenAIRE

Xin Zhao; G. Ciovati; T. R. Bieler

2010-01-01

The performance of superconducting radio-frequency (SRF) resonant cavities made of bulk niobium is limited by nonlinear localized effects. Surface analysis of regions of higher power dissipation is thus of intense interest. Such areas (referred to as “hotspots”) were identified in a large-grain single-cell cavity that had been buffered-chemical polished and dissected for examination by high resolution electron microscopy, electron backscattered diffraction microscopy (EBSD), and optical micro...

Relative Age Effect and Academic Timing in American Junior College Baseball.

Science.gov (United States)

Beals, Thomas C; Furtado, Ovande; Fontana, Fabio E

2018-02-01

Previous research has shown that older athletes within age groupings are often perceived to be more talented simply due to advanced maturity, leading to biased selection in higher levels of sports competition, now commonly termed relative age effect (RAE). This study's goals were to determine whether (a) RAE influenced the selection of junior college baseball participants and (b) academic timing ( Glamser & Marciani, 1992 ), in which academic status determines age groupings more than strict age guidelines for college sports, influenced the formation of RAE. Participants were 150 junior college baseball players. Our results showed that RAE was only a significant factor, comparing the birth distribution of participants born before and after the midpoint of the participation year, when academic timing was also a factor in determining age groupings. In addition, the birth rate distribution, though not significantly different than expected, was greater only when those participants born during the expected participation year were included. The results of this study indicate that RAE could bear more influence among American student-athletes than was previously reported in that RAE in conjunction with academic timing does influence the selection of collegiate athletes.

Unaccounted Workload Factor: Game-Day Pitch Counts in High School Baseball Pitchers—An Observational Study

Science.gov (United States)

Zaremski, Jason L.; Zeppieri, Giorgio; Jones, Deborah L.; Tripp, Brady L.; Bruner, Michelle; Vincent, Heather K.; Horodyski, MaryBeth

2018-01-01

Background: Throwing injuries are common in high school baseball. Known risk factors include excessive pitch counts, year-round pitching, and pitching with arm pain and fatigue. Despite the evidence, the prevalence of pitching injuries among high school players has not decreased. One possibility to explain this pattern is that players accumulate unaccounted pitch volume during warm-up and bullpen activity, but this has not yet been examined. Hypotheses: Our primary hypothesis was that approximately 30% to 40% of pitches thrown off a mound by high school pitchers during a game-day outing are unaccounted for in current data but will be revealed when bullpen sessions and warm-up pitches are included. Our secondary hypothesis was that there is wide variability among players in the number of bullpen pitches thrown per outing. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Researchers counted all pitches thrown off a mound during varsity high school baseball games played by 34 high schools in North Central Florida during the 2017 season. Results: We recorded 13,769 total pitches during 115 varsity high school baseball starting pitcher outings. The mean ± SD pitch numbers per game were calculated for bullpen activity (27.2 ± 9.4), warm-up (23.6 ±8.0), live games (68.9 ±19.7), and total pitches per game (119.7 ± 27.8). Thus, 42.4% of the pitches performed were not accounted for in the pitch count monitoring of these players. The number of bullpen pitches thrown varied widely among players, with 25% of participants in our data set throwing fewer than 22 pitches and 25% throwing more than 33 pitches per outing. Conclusion: In high school baseball players, pitch count monitoring does not account for the substantial volume of pitching that occurs during warm-up and bullpen activity during the playing season. These extra pitches should be closely monitored to help mitigate the risk of overuse injury. PMID:29662911

Unaccounted Workload Factor: Game-Day Pitch Counts in High School Baseball Pitchers-An Observational Study.

Science.gov (United States)

Zaremski, Jason L; Zeppieri, Giorgio; Jones, Deborah L; Tripp, Brady L; Bruner, Michelle; Vincent, Heather K; Horodyski, MaryBeth

2018-04-01

Throwing injuries are common in high school baseball. Known risk factors include excessive pitch counts, year-round pitching, and pitching with arm pain and fatigue. Despite the evidence, the prevalence of pitching injuries among high school players has not decreased. One possibility to explain this pattern is that players accumulate unaccounted pitch volume during warm-up and bullpen activity, but this has not yet been examined. Our primary hypothesis was that approximately 30% to 40% of pitches thrown off a mound by high school pitchers during a game-day outing are unaccounted for in current data but will be revealed when bullpen sessions and warm-up pitches are included. Our secondary hypothesis was that there is wide variability among players in the number of bullpen pitches thrown per outing. Cross-sectional study; Level of evidence, 3. Researchers counted all pitches thrown off a mound during varsity high school baseball games played by 34 high schools in North Central Florida during the 2017 season. We recorded 13,769 total pitches during 115 varsity high school baseball starting pitcher outings. The mean ± SD pitch numbers per game were calculated for bullpen activity (27.2 ± 9.4), warm-up (23.6 ±8.0), live games (68.9 ±19.7), and total pitches per game (119.7 ± 27.8). Thus, 42.4% of the pitches performed were not accounted for in the pitch count monitoring of these players. The number of bullpen pitches thrown varied widely among players, with 25% of participants in our data set throwing fewer than 22 pitches and 25% throwing more than 33 pitches per outing. In high school baseball players, pitch count monitoring does not account for the substantial volume of pitching that occurs during warm-up and bullpen activity during the playing season. These extra pitches should be closely monitored to help mitigate the risk of overuse injury.

Outcomes and Return to Sport After Ulnar Collateral Ligament Reconstruction in Adolescent Baseball Players.

Science.gov (United States)

Saper, Michael; Shung, Joseph; Pearce, Stephanie; Bompadre, Viviana; Andrews, James R

2018-04-01

The number of ulnar collateral ligament (UCL) reconstructions in adolescent athletes has increased over the past 2 decades. Clinical results in this population have not been well studied. The purpose of this study was to evaluate the outcomes and return to sport after UCL reconstruction in a large group of adolescent baseball players. We hypothesized that excellent clinical outcomes and high rates of return to sport would be observed in this population at a minimum 2-year follow-up. Case series; Level of evidence, 4. We reviewed 140 adolescent (aged ≤19 years) baseball players who underwent UCL reconstruction with the American Sports Medicine Institute (ASMI) technique by a single surgeon. Medical records were reviewed for patient demographics, injury characteristics, operative details, and surgical complications. Patient-reported outcomes were assessed using the Conway scale, the Andrews-Timmerman (A-T) score, the Kerlan-Jobe Orthopaedic Clinic (KJOC) score, and a 0- to 100-point subjective scale for elbow function and satisfaction. Return to sporting activity was assessed using a custom-designed questionnaire. The mean age at the time of surgery was 18.0 years (range, 13-19 years), and the mean follow-up was 57.9 months (range, 32.4-115.4 months). Over half (60%) of patients were high school athletes. The mean duration of symptoms before surgery was 6.9 months (range, 0.5-60.0 months). Partial tears were identified in 57.9% of patients, and 41.3% of patients had preoperative ulnar nerve symptoms. Graft type included the ipsilateral palmaris in 77.1% of patients. Concomitant procedures were performed in 25% of patients. Outcomes on the Conway scale were "excellent" in 86.4% of patients. The mean A-T and KJOC scores were 97.3 ± 6.1 and 85.2 ± 14.6, respectively. Mean patient satisfaction was 94.4. Overall, 97.8% of patients reported returning to sport at a mean of 11.6 months (range, 5-24 months), and 89.9% of patients returned to sport at the same level of

Superconducting magnet development in Japan

International Nuclear Information System (INIS)

Yasukochi, K.

1983-01-01

The present state of R and D works on the superconducting magnet and its applications in Japan are presented. On electrical rotating machines, 30 MVA superconducting synchronous rotary condenser (Mitsubishi and Fuji) and 50 MVA generator are under construction. Two ways of ship propulsion by superconducting magnets are developing. A superconducting magnetically levitated and linear motor propelled train ''MAGLEV'' was developed by the Japan National Railways (JNR). The superconducting magnet development for fusion is the most active field in Japan. The Cluster Test program has been demonstrated on a 10 T Nb 3 Sn coil and the first coil of Large Coil Task in IEA collaboration has been constructed and the domestic test was completed in JAERI. These works are for the development of toroidal coils of the next generation tokamak machine. R and D works on superconducting ohmic heating coil are in progress in JAERI and ETL. The latter group has constructed 3.8 MJ pulsed coil. A high ramp rate of changing field in pulsed magnet, 200 T/s, has been tested successfully. High Energy Physics Laboratory (KEK) are conducting active works. The superconducting μ meson channel and π meson channel have been constructed and are operating successfully. KEK has also a project of big accelerator named ''TRISTAN'', which is similar to ISABELLE project of BNL. Superconducting synchrotron magnets are developed for this project. The development of superconducting three thin wall solenoid has been started. One of them, CDF, is progressing under USA-Japan collaboration

Protection of large-stored-energy superconducting coils

International Nuclear Information System (INIS)

Kircher, F.

1975-11-01

When the stored energy of superconducting magnets increases, the problem of the protection of the coil when a quench occurs becomes more and more important, especially if the structure of the coil is such that the energy can be dissipated only in a small part of the coil. The aim of this paper is first to describe a program which enables to predict the increase of temperature inside the coil for several kinds of protection and to give results for KEK pulsed dipoles (under construction and planned for TRISTAN). (auth.)

Instructional Design for Accelerated Macrocognitive Expertise in the Baseball Workplace.

Science.gov (United States)

Fadde, Peter J

2016-01-01

The goal of accelerating expertise can leave researchers and trainers in human factors, naturalistic decision making, sport science, and expertise studies concerned about seemingly insufficient application of expert performance theories, findings and methods for training macrocognitive aspects of human performance. Video-occlusion methods perfected by sports expertise researchers have great instructional utility, in some cases offering an effective and inexpensive alternative to high-fidelity simulation. A key problem for instructional designers seems to be that expertise research done in laboratory and field settings doesn't get adequately translated into workplace training. Therefore, this article presents a framework for better linkage of expertise research/training across laboratory, field, and workplace settings. It also uses a case study to trace the development and implementation of a macrocognitive training program in the very challenging workplace of the baseball batters' box. This training, which was embedded for a full season in a college baseball team, targeted the perceptual-cognitive skill of pitch recognition that allows expert batters to circumvent limitations of human reaction time in order to hit a 90 mile-per-hour slider. While baseball batting has few analogous skills outside of sports, the instructional design principles of the training program developed to improve batting have wider applicability and implications. Its core operational principle, supported by information processing models but challenged by ecological models, decouples the perception-action link for targeted part-task training of the perception component, in much the same way that motor components routinely are isolated to leverage instructional efficiencies. After targeted perceptual training, perception and action were recoupled via transfer-appropriate tasks inspired by in situ research tasks. Using NCAA published statistics as performance measures, the cooperating team

Instructional Design for Accelerated Macrocognitive Expertise in the Baseball Workplace

Directory of Open Access Journals (Sweden)

Peter J. Fadde

2016-03-01

Full Text Available The goal of accelerating expertise can leave researchers and trainers in human factors, naturalistic decision making, sport science, and expertise studies concerned about seemingly insufficient application of expert performance theories, findings and methods for training macrocognitive aspects of human performance. Video-occlusion methods perfected by sports expertise researchers have great instructional utility, in some cases offering an effective and inexpensive alternative to high-fidelity simulation. A key problem for instructional designers seems to be that expertise research done in laboratory and field settings doesn’t get adequately translated into workplace training. Therefore, this article presents a framework for better linkage of expertise research/training across laboratory, field, and workplace settings. It also uses a case study to trace the development and implementation of a macrocognitive training program in the very challenging workplace of the baseball batters’ box. This training, which was embedded for a full season in a college baseball team, targeted the perceptual-cognitive skill of pitch recognition that allows expert batters to circumvent limitations of human reaction time in order to hit a 90 mile-per-hour slider. While baseball batting has few analogous skills outside of sports, the instructional design principles of the training program developed to improve batting have wider applicability and implications. Its core operational principle, supported by information processing models but challenged by ecological models, decouples the perception-action link for targeted part-task training of the perception component, in much the same way that motor components routinely are isolated to leverage instructional efficiencies. After targeted perceptual training, perception and action were recoupled via transfer-appropriate tasks inspired by in situ research tasks. Using NCAA published statistics as performance measures

Superconducting generator technology--an overview

International Nuclear Information System (INIS)

Edmonda, J.S.

1979-01-01

Application of superconducting technology to field windings of large ac generators provides virtually unlimited field capability without incurring resistive losses in the winding. Several small-scale superconducting generators have been built and tested demonstrating the feasibility of such concepts. For machines of much larger capacity, conceptual designs for 300 Mva and 1200 Mva have been completed. The development of a 300 Mva generator is projected. Designed, engineered and fabricated as a turbo generator, the superconducting machine is to be installed in a power plant, tested and operated in concert with a prime mover, the steam generator and the auxiliary support systems of the power plant. This will provide answers to the viability of operating a superconducting machine and its cryogenic handling systems in a full time, demanding environment. 21 refs

Superconducting coaxial cable as a large capacity transmission medium for communication

International Nuclear Information System (INIS)

Mikoshiba, K.; Simohori, Y.; Ohmori, N.; Sone, F.

1974-01-01

In order to survey the feasibility of the superconducting communication system, the electrical performance of superconducting coaxial cable has been investigated experimentally. The results are as follows. The transmission loss can be described as a function of the frequency, a(f) = a 1 f 2 + a 2 f. Dielectric loss is dominant up to a few gigahertz. Improvement of the impedance irregularities due to dimensional imperfections along the cable smoothens the transmission loss versus frequency characteristics. The temperature dependence of the transmission loss agrees well with an approximate expression deduced using the Pippard temperature function. (author)

Superconductivity in domains with corners

DEFF Research Database (Denmark)

Bonnaillie-Noel, Virginie; Fournais, Søren

2007-01-01

We study the two-dimensional Ginzburg-Landau functional in a domain with corners for exterior magnetic field strengths near the critical field where the transition from the superconducting to the normal state occurs. We discuss and clarify the definition of this field and obtain a complete...... asymptotic expansion for it in the large $\\kappa$ regime. Furthermore, we discuss nucleation of superconductivity at the boundary....

Melt formed superconducting joint between superconducting tapes

International Nuclear Information System (INIS)

Benz, M.G.; Knudsen, B.A.; Rumaner, L.E.; Zaabala, R.J.

1992-01-01

This patent describes a superconducting joint between contiguous superconducting tapes having an inner laminate comprised of a parent-metal layer selected from the group niobium, tantalum, technetium, and vanadium, a superconductive intermetallic compound layer on the parent-metal layer, a reactive-metal layer that is capable of combining with the parent-metal and forming the superconductive intermetallic compound, the joint comprising: a continuous precipitate of the superconductive intermetallic compound fused to the tapes forming a continuous superconducting path between the tapes

Design considerations for high-current superconducting ion linacs

International Nuclear Information System (INIS)

Delayen, J.R.; Bohn, C.L.; Micklich, B.J.; Roche, C.T.; Sagalovsky, L.

1993-01-01

Superconducting linacs may be a viable option for high-current applications such as fusion materials irradiation testing, spallation neutron source, transmutation of radioactive waste, tritium production, and energy production. These linacs must run reliably for many years and allow easy routine maintenance. Superconducting cavities operate efficiently with high cw gradients, properties which help to reduce operating and capital costs, respectively. However, cost-effectiveness is not the sole consideration in these applications. For example, beam impingement must be essentially eliminated to prevent unsafe radioactivation of the accelerating structures, and thus large apertures are needed through which to pass the beam. Because of their high efficiency, superconducting cavities can be designed with very large bore apertures, thereby reducing the effect of beam impingement. Key aspects of high-current cw superconducting linac designs are explored in this context

Superconducting linear accelerator cryostat

International Nuclear Information System (INIS)

Ben-Zvi, I.; Elkonin, B.V.; Sokolowski, J.S.

1984-01-01

A large vertical cryostat for a superconducting linear accelerator using quarter wave resonators has been developed. The essential technical details, operational experience and performance are described. (author)

Trunk Muscle Function Deficit in Youth Baseball Pitchers With Excessive Contralateral Trunk Tilt During Pitching.

Science.gov (United States)

Oyama, Sakiko; Waldhelm, Andrew G; Sosa, Araceli R; Patel, Ravina R; Kalinowski, Derick L

2017-09-01

Pitching technique is one of many factors that affect injury risk. Exhibiting excessive contralateral trunk tilt (CLT) during pitching has been linked to higher ball speed but also to increased joint loading. Deficit in trunk muscle strength has been suggested as an underlying cause of this movement pattern. The purpose of the study was to compare trunk muscle strength between youth baseball pitchers with varying degree of CLT during pitching. Cross-sectional study. Baseball practice fields. Twenty-eight youth baseball pitchers. Pitching technique was captured using a video camera. Based on the 2-dimensional trunk contralateral flexion angle, pitchers were categorized into low (30 degrees) CLT groups. Maximum isometric strength tests for trunk flexion, extension, and bilateral rotation, measured using a dynamometer. The pitchers with high CLT (n = 10) had longer pitching experience (P = 0.014), produced higher ball speed (P = 0.003) compared with the pitchers with moderate (n = 10) and low (n = 8) CLT, but demonstrated greater asymmetry in trunk rotation strength (relative weakness in rotation strength toward dominant side) compared with the pitchers with low CLT (P = 0.015). Excessive CLT may be a strategy that young pitchers learn to achieve higher ball velocity but also may be associated with imbalance between the oblique muscles on dominant and nondominant side, which may be acquired from repetitive pitching. Strengthening and emphasizing the use of dominant side oblique muscles may keep pitchers from leaning excessively during pitching and thus decrease joint loading.

Considerations of coil protection and electrical connection schemes in large superconducting toroidal magnet system

International Nuclear Information System (INIS)

Yeh, H.T.

1976-03-01

A preliminary comparison of several different coil protection and electrical connection schemes for large superconducting toroidal magnet systems (STMS) is carried out. The tentative recommendation is to rely on external dump resistors for coil protection and to connect the coils in the toroidal magnet in several parallel loops (e.g., every fourth coil is connected into a single series loop). For the fault condition when a single coil quenches, the quenched coil should be isolated from its loop by switching devices. The magnet, as a whole, should probably be discharged if more than a few coils have quenched

Design and fabrication of forced-flow superconducting poloidal coils for the Large Helical Device

International Nuclear Information System (INIS)

Nakamoto, K.; Yamamoto, T.; Mizumaki, S.; Yamakoshi, T.; Kanai, Y.; Yamamoto, K.; Wachi, Y.; Ushijima, M.; Yoshida, T.; Kai, T.; Takahata, K.; Yamamoto, J.; Satow, T.; Motojima, O.

1995-01-01

Three pairs of superconducting poloidal coils for the LHD (Large Helical Device) have been designed and fabricated using NbTi/Cu cable-in-conduit (CIC) conductors cooled with forced-flow supercritical helium (SHE). In the LHD poloidal coils, high field accuracy as well as high reliability are required. To meet these requirements, detailed field and structural analyses have been performed and key parameters including winding pattern and size and locations of conductor joints have been determined. Compact conductor joint, where NbTi filaments are directly bonded, has also been developed using the solid state bonding technique. (orig.)

Superconducting current generators

International Nuclear Information System (INIS)

Genevey, P.

1970-01-01

After a brief summary of the principle of energy storage and liberation with superconducting coils,two current generators are described that create currents in the range 600 to 1400 A, used for two storage experiments of 25 kJ and 50 kJ respectively. The two current generators are: a) a flux pump and b) a superconducting transformer. Both could be developed into more powerful units. The study shows the advantage of the transformer over the flux pump in order to create large currents. The efficiencies of the two generators are 95 per cent and 40 to 60 per cent respectively. (author) [fr

Tore-Supra: a Tokamak with superconducting toroidal field coils

International Nuclear Information System (INIS)

Turck, B.

1987-07-01

Tore Supra is a tokamak under construction on the site of Cen Cadarache by the Euratom-CEA Association. The machine technology integrates all problems related to the fabrication and the operation of large superconducting coils and of the associated cryogenic system. Tore Supra will provide a significant experience to prepare the next generation of machines for plasma physics and controlled fusion. Tore Supra is specially designed to implement a large physics program. The superconducting coils make possible the study of plasma confinement in long pulses (more than 60s), the impurities and the stability, and the efficiency of additional heating sources (neutral particle beams and radio frequency heating). The opportunity is taken to recall the particular features and requirements of the superconducting coils of the large future tokamaks in order to point out the problems that have to be faced by any new material (superconducting or not)

Streaming-plasma measurements in the Baseball II-T mirror experiment

International Nuclear Information System (INIS)

Damm, C.C.; Foote, J.H.; Futch, A.H.; Goodman, R.K.; Hornady, R.S.; Osher, J.E.; Porter, G.D.

1977-01-01

The warm plasma from a deuterium-loaded titanium washer gun, streaming along magnetic-field lines through the steady-state magnetic well of Baseball II, has been examined for its suitability in this experimental situation as a target plasma for hot-ion buildup experiments and for microinstability control. The gun was positioned near the magnetic axis outside the mirror region. Measurements were made with gridded, end-loss detectors placed outside the opposite mirror, a microwave interferometer, a beam-attenuation detector, and other diagnostics

Effect on High versus Low Fidelity Haptic Feedback in a Virtual Reality Baseball Simulation

DEFF Research Database (Denmark)

Ryge, Andreas Nicolaj; Thomsen, Lui Albæk; Berthelsen, Theis

2017-01-01

In this paper we present a within-subjects study (n=26) comparing participants' experience of three kinds of haptic feedback (no haptic feedback, low fidelity haptic feedback and high fidelity haptic feedback) simulating the impact between a virtual baseball bat and ball. We noticed some minor ef...

Status of superconducting magnet development (SSC, RHIC, LHC)

International Nuclear Information System (INIS)

Wanderer, P.

1993-01-01

This paper summarizes recent superconducting accelerator magnet construction and test activities at the Superconducting Super Collider Laboratory (SSC), the Large Hardon Collider at CERN (LHC), and the Relativistic Heavy Ion Collider at Brookhaven (RHIC). Future plans are also presented

Status of superconducting magnet development (SSC, RHIC, LHC)

International Nuclear Information System (INIS)

Wanderer, P.

1993-01-01

This paper summarize recent superconducting accelerator magnet construction and test activities at the Superconducting Super Collider Laboratory (SSC), the Large Hadron Collider at CERN (LHC), and the Relativistic Heavy Ion Collider at Brookhaven (RHIC). Future plan are also presented

DIFFERENTIATION OF BODY COMPOSITION OF PLAYERS OF THE POLISH NATIONAL BASEBALL TEAM

Directory of Open Access Journals (Sweden)

Marina Jagiełło

2014-10-01

Full Text Available The purpose of the study is to identify the differentiation of body composition among players of Polish national baseball team in comparison to persons of the same population not professionally engaged in sport. The study involved Polish baseball representatives (n=20. Competitors’ age was 18-28 years, body mass from 67.7 kg to 114 kg (85±10.3 kg, and body height 173-196 cm (185.1±4.8. The training experience was 7-14 years and it was highly differentiated. The stoutness factor is the dominant factor among "infielders" and "pitchers", and among "outfielders" - the length one. The proportions of the features within the factors show that players are characterized by a strongly muscled forearm and a shank and by a clear predominance of the elbow width with a disproportionately - to the overall size of the factor - small knee and shoulder width. In the length factor an even contribution of the upper and lower extremity length with lower sitting body height can be noted. Depending on the position on the field there is a differentiation of the internal proportions of the body.

Superconductivity

CERN Document Server

Poole, Charles P; Farach, Horacio A

1995-01-01

Superconductivity covers the nature of the phenomenon of superconductivity. The book discusses the fundamental principles of superconductivity; the essential features of the superconducting state-the phenomena of zero resistance and perfect diamagnetism; and the properties of the various classes of superconductors, including the organics, the buckministerfullerenes, and the precursors to the cuprates. The text also describes superconductivity from the viewpoint of thermodynamics and provides expressions for the free energy; the Ginzburg-Landau and BCS theories; and the structures of the high

Smokeless tobacco use and health effects among baseball players.

Science.gov (United States)

Ernster, V L; Grady, D G; Greene, J C; Walsh, M; Robertson, P; Daniels, T E; Benowitz, N; Siegel, D; Gerbert, B; Hauck, W W

1990-07-11

The effects of smokeless tobacco (ST) use were studied in 1109 members of major and minor league professional baseball teams during spring training in 1988. The prevalence of current ST use was 39%. The median age at initiation among users was 18 years, and the median duration of use was 5 years. Among users, 75% cited a snuff brand as their usual ST product. Oral leukoplakia was present in 46% (196/423) of current-week ST users and 1.4% (7/493) of nonusers (odds ratio, 60; 95% confidence interval, 28 to 130). Prevalence of oral leukoplakia among ST users increased with hours used per day and decreased with time lapsed since last use, and was higher in snuff users than in chewing tobacco users. Of the subjects with oral leukoplakia who underwent punch biopsy, 91 had benign hyperkeratosis and one had mild dysplasia. Overall prevalence of dental caries, gingivitis, and plaque did not differ between ST users and nonusers. In analyses confined to facial surfaces of mandibular incisor teeth, where ST is most commonly used, there were significant increases among users in both gingival recession and attachment loss. Users of ST did not differ from nonusers in blood pressure, pulse, total or high-density lipoprotein cholesterol level, or white blood cell count, but among users high-density lipoprotein cholesterol levels were inversely associated with serum cotinine levels. The major health effects of ST use among professional baseball players are oral leukoplakia and localized periodontal disease. The study population was young, physically fit, and characterized by relatively moderate short-term ST use.

Operation of a forced two phase cooling system on a large superconducting magnet

International Nuclear Information System (INIS)

Green, M.A.; Burns, W.A.; Eberhard, P.H.; Gibson, G.H.; Pripstein, M.; Ross, R.R.; Smits, R.G.; Taylor, J.D.; Van Slyke, H.

1980-05-01

This paper describes the operation of a forced two phase cooling system on a two meter diameter superconducting solenoid. The magnet is a thin high current density superconducting solenoid which is cooled by forced two phase helium in tubes around the coil. The magnet, which is 2.18 meters in diameter and 3.4 meters long, has a cold mass of 1700 kg. The two phase cooling system contains less than 300 liters of liquid helium, most of which is contained in a control dewar. This paper describes the operating characteristics of the LBL two phase forced cooling system during cooldown and warm up. The paper presents experimental data on operations of the magnet using either a helium pump or the refrigerator compressor to circulate two phase helium through the superconducting coil cooling tubes

Baseball Stadium Design: Teaching Engineering Economics and Technical Communication in a Multi-Disciplinary Setting.

Science.gov (United States)

Dahm, Kevin; Newell, James

2001-01-01

Reports on a course at Rowan University, based on the economic design of a baseball stadium, that offers an introduction to multidisciplinary engineering design linked with formal training in technical communication. Addresses four pedagogical goals: (1) developing public speaking skills in a realistic, business setting; (2) giving students…

Energy-efficient electrical machines by new materials. Superconductivity in large electrical machines

International Nuclear Information System (INIS)

Frauenhofer, Joachim; Arndt, Tabea; Grundmann, Joern

2013-01-01

The implementation of superconducting materials in high-power electrical machines results in significant advantages regarding efficiency, size and dynamic behavior when compared to conventional machines. The application of HTS (high-temperature superconductors) in electrical machines allows significantly higher power densities to be achieved for synchronous machines. In order to gain experience with the new technology, Siemens carried out a series of development projects. A 400 kW model motor for the verification of a concept for the new technology was followed by a 4000 kV A generator as highspeed machine - as well as a low-speed 4000 kW propeller motor with high torque. The 4000 kVA generator is still employed to carry out long-term tests and to check components. Superconducting machines have significantly lower weight and envelope dimensions compared to conventional machines, and for this reason alone, they utilize resources better. At the same time, operating losses are slashed to about half and the efficiency increases. Beyond this, they set themselves apart as a result of their special features in operation, such as high overload capability, stiff alternating load behavior and low noise. HTS machines provide significant advantages where the reduction of footprint, weight and losses or the improved dynamic behavior results in significant improvements of the overall system. Propeller motors and generators,for ships, offshore plants, in wind turbine and hydroelectric plants and in large power stations are just some examples. HTS machines can therefore play a significant role when it comes to efficiently using resources and energy as well as reducing the CO 2 emissions.

Difference in Functional Performance on the Upper-Quarter Y-Balance Test Between High School Baseball Players and Wrestlers.

Science.gov (United States)

Myers, Heather; Poletti, Mary; Butler, Robert J

2017-05-01

The Upper Quarter Y-Balance Test (YBT-UQ) is a unique movement test where individuals perform at the limits of their stability, requiring the coordination of balance, proprioception, range of motion, and stabilization. It is not yet clear if performance on the YBT-UQ differs between sports with dissimilar emphasis on upper-extremity performance. To compare performance on the YBT-UQ between wrestlers, whose sport requires some degree of closed-chain activity, and baseball players, whose sport is primarily open kinetic chain in nature. Cross-sectional. High school preparticipation physical assessment. 24 healthy high school male wrestlers (mean age 16.12 ± 1.24 y) and 24 healthy high school male baseball players (mean age 15.79 ± 1.25 y). All subjects performed the YBT-UQ, which requires reaching in 3 directions while maintaining a push-up position. The variables of interest include the maximum reach in each direction, as well as the composite score. In addition, asymmetries between limbs for each reach direction were compared. Wrestlers performed significantly better than baseball players in the medial direction, inferolateral direction, and in composite scores. In the medial direction, wrestlers exhibited greater scores (P < .01) on both left and right limbs, 10.5 ± 10.2%LL and 9.95 ± 10.2%LL, respectively. Significant differences (P < .01) were also observed in the inferolateral direction, with a difference of 11.3 ± 12.0%LL on the left and 8.7 ± 11.0%LL on the right. Composite scores were higher (P < .01) for the wrestlers, with a difference of 7.0% on the left and 7.1% on the right. This study suggests that wrestlers perform better on the YBT-UQ than baseball players. The findings may suggest sport-specific normative data for the YBT-UQ in high school athletes.

Superconductivity and antiferromagnetism in heavy-electron systems

International Nuclear Information System (INIS)

Konno, R.; Ueda, K.

1989-01-01

Superconductivity and antiferromagnetism in heavy-electron systems are investigated from a general point of view. First we classify superconducting states in a simple cubic lattice, a body-centered tetragonal lattice, and a hexagonal close-packed lattice, having URu 2 Si 2 and UPt 3 in mind. For that purpose we take an approach to treat the effective couplings in real space. The approach is convenient to discuss the relation between the nature of fluctuations in the system and the superconducting states. When we assume that the antiferromagnetic fluctuations reported by neutron experiments are dominant, the most promising are some of the anisotropic singlet states and there remains the possibility for some triplet states too. Then we discuss the coupling between the two order parameters based on a Ginzburg-Landau theory. We derive a general expression of the coupling term. It is pointed out that the coupling constant can be large in heavy-electron systems. The general trend of the coexistence of the superconductivity and antiferromagnetism is discussed, and it is shown that the anisotropic states are generally more favorable to the coexistence than the conventional isotropic singlet. Experimental data of URu 2 Si 2 and UPt 3 are analyzed by the Ginzburg-Landau theory. According to the analysis URu 2 Si 2 has a small coupling constant and a large condensation energy of the antiferromagnetism. On the other hand, UPt 3 has a large coupling constant and a small condensation energy. It means that the specific-heat anomaly at T N should be small in UPt 3 and its superconductivity is easily destroyed when a large moment is formed

Apparent destruction of superconductivity in the disordered one-dimensional limit

International Nuclear Information System (INIS)

Graybeal, J.M.; Mankiewich, P.M.; Dynes, R.C.; Beasley, M.R.

1987-01-01

We present the results of a model-system study of the competition between superconductivity and disorder in narrow superconducting wires. As one moves from the two-dimensional regime toward the one-dimensional limit, large and systematic reductions in the superconducting transition temperature are obtained. The observed behavior extrapolates to the total destruction of superconductivity in the disordered one-dimensional limit. Our findings are in clear disagreement with a recent theoretical treatment. In addition, the superconducting fluctuations appear to be modified by disorder for the narrowest samples

Superconducting magnetic energy storage, possibilities and limitations

International Nuclear Information System (INIS)

Bace, M.; Knapp, V.

1981-01-01

Energy storage is of great importance for the exploitation of new energy sources as well as for the better utilisation of conventional ones. Several proposals in recent years have suggested that superconducting magnets could be used as energy storage in large electricity networks. It is a purpose of this note to point out that the requirements which have to be met by energy storage in a large electricity network place serious limitation on the possible use of superconducting energy storage. (author)

Relationship Between the Relative Age Effect and Lengths of Professional Careers in Male Japanese Baseball Players: a Retrospective Analysis.

Science.gov (United States)

Nakata, Hiroki

2017-12-01

The mechanisms underlying the relative age effect in sport events have been investigated for more than two decades. The present study focused on the relationship between the relative age effect and lengths of professional careers among professional male Japanese baseball players. The birth dates of players and lengths of professional careers were collected from an official publication, and data were divided into four quarters (Q1: April-June; Q2: July-September; Q3: October-December; Q4: January-March of the following year) grouped by 3 years. Based on the data for Q4, the expected numbers for the lengths of professional careers were calculated for Q1, Q2, and Q3. The number of players with professional careers of more than 19 years was significantly smaller in Q4 than in Q1, Q2, and Q3. The relative age effect among professional male Japanese baseball players was associated with the lengths of professional careers. Relative age appears to be a very important factor for the development of expertise among male Japanese baseball players and involves long-term disadvantages after becoming professional players.

Collective modes in superconducting rhombohedral graphite

Energy Technology Data Exchange (ETDEWEB)

Kauppila, Ville [O.V. Lounasmaa Laboratory, Aalto University (Finland); Hyart, Timo; Heikkilae, Tero [University of Jyvaeskylae (Finland)

2015-07-01

Recently it was realized that coupling particles with a Dirac dispersion (such as electrons in graphene) can lead to a topologically protected state with flat band dispersion. Such a state could support superconductivity with unusually high critical temperatures. Perhaps the most promising way to realize such coupling in real materials is in the surface of rhombohedrally stacked graphite. We consider collective excitations (i.e. the Higgs modes) in surface superconducting rhombohedral graphite. We find two amplitude and two phase modes corresponding to the two surfaces of the graphite where the superconductivity lives. We calculate the dispersion of these modes. We also derive the Ginzburg-Landau theory for this material. We show that in superconducting rhombohedral graphite, the collective modes, unlike in conventional BCS superconductors, give a large contribution to thermodynamic properties of the material.

Foreword: Focus on Superconductivity in Semiconductors

Directory of Open Access Journals (Sweden)

Yoshihiko Takano

2008-01-01

Full Text Available Since the discovery of superconductivity in diamond, much attention has been given to the issue of superconductivity in semiconductors. Because diamond has a large band gap of 5.5 eV, it is called a wide-gap semiconductor. Upon heavy boron doping over 3×1020 cm−3, diamond becomes metallic and demonstrates superconductivity at temperatures below 11.4 K. This discovery implies that a semiconductor can become a superconductor upon carrier doping. Recently, superconductivity was also discovered in boron-doped silicon and SiC semiconductors. The number of superconducting semiconductors has increased. In 2008 an Fe-based superconductor was discovered in a research project on carrier doping in a LaCuSeO wide-gap semiconductor. This discovery enhanced research activities in the field of superconductivity, where many scientists place particular importance on superconductivity in semiconductors.This focus issue features a variety of topics on superconductivity in semiconductors selected from the 2nd International Workshop on Superconductivity in Diamond and Related Materials (IWSDRM2008, which was held at the National Institute for Materials Science (NIMS, Tsukuba, Japan in July 2008. The 1st workshop was held in 2005 and was published as a special issue in Science and Technology of Advanced Materials (STAM in 2006 (Takano 2006 Sci. Technol. Adv. Mater. 7 S1.The selection of papers describe many important experimental and theoretical studies on superconductivity in semiconductors. Topics on boron-doped diamond include isotope effects (Ekimov et al and the detailed structure of boron sites, and the relation between superconductivity and disorder induced by boron doping. Regarding other semiconductors, the superconducting properties of silicon and SiC (Kriener et al, Muranaka et al and Yanase et al are discussed, and In2O3 (Makise et al is presented as a new superconducting semiconductor. Iron-based superconductors are presented as a new series of high

Development of 50 MVA superconducting generator

International Nuclear Information System (INIS)

Ueda, Kiyotaka; Maki, Naoki; Takahashi, Noriyoshi; Ogata, Hisanao; Sanematsu, Toshihiro.

1984-01-01

Superconducting synchronous generators are expected to be the large capacity turbogenerators of next generation, but they have the structural features considerably different from conventional generators, such as low temperature multiple cylinder rotors and air gap armature winding. For the purpose of grasping the performance of superconducting generators and establishing the fundamental technology for their practical use, Hitachi Ltd. manufactured a 50 MVA superconducting generator. As the results of test, the precooling operation was smoothly finished for about 40 hours, and the superconducting rotor rotated stably at 3000 rpm. The steady and transient electrical characteristics were able to be grasped. It is intended to reflect these results to the development of a practical generator of 500 MVA class expected as the next step. When the superconducting exciting winding cooled by liquid helium is used, the reduction of weight, the improvement of efficiency and the improvement of the stability of power system can be expected. The structural features and the function of superconducting generators, the present state of the development in the world, the outline of the 50 MVA generator, the test results and the problems and the prospect hereafter are reported. The superconducting winding was made of NbTiZr alloy multicore wires. (Kako, I.)

Frozen ammonia micropellet generator for Baseball II-T

International Nuclear Information System (INIS)

Denhoy, B.S.

1975-01-01

A ''startup'' plasma at the center of the Baseball II-T magnet was studied. This startup plasma will be used as a target for high energy neutral beams to achieve the required build-up. The target plasma will be created by irradiating a solid pellet with a laser beam. Although a deuterium pellet would be superior because of purity, the development of an ammonia pellet was undertaken because it requires a simpler technology. The ammonia target plasma is physically acceptable for the initial experiment. A frozen ammonia pellet, about 100 μm in diameter, will be irradiated with 300-J CO 2 laser, to produce a density of about 10 13 cm -3 and about 1 kV temperature

Superconductivity

International Nuclear Information System (INIS)

Taylor, A.W.B.; Noakes, G.R.

1981-01-01

This book is an elementray introduction into superconductivity. The topics are the superconducting state, the magnetic properties of superconductors, type I superconductors, type II superconductors and a chapter on the superconductivity theory. (WL)

Superconductivity

International Nuclear Information System (INIS)

Onnes, H.K.

1988-01-01

The author traces the development of superconductivity from 1911 to 1986. Some of the areas he explores are the Meissner Effect, theoretical developments, experimental developments, engineering achievements, research in superconducting magnets, and research in superconducting electronics. The article also mentions applications shown to be technically feasible, but not yet commercialized. High-temperature superconductivity may provide enough leverage to bring these applications to the marketplace

Superconductivity

International Nuclear Information System (INIS)

Andersen, N.H.; Mortensen, K.

1988-12-01

This report contains lecture notes of the basic lectures presented at the 1st Topsoee Summer School on Superconductivity held at Risoe National Laboratory, June 20-24, 1988. The following lecture notes are included: L.M. Falicov: 'Superconductivity: Phenomenology', A. Bohr and O. Ulfbeck: 'Quantal structure of superconductivity. Gauge angle', G. Aeppli: 'Muons, neutrons and superconductivity', N.F. Pedersen: 'The Josephson junction', C. Michel: 'Physicochemistry of high-T c superconductors', C. Laverick and J.K. Hulm: 'Manufacturing and application of superconducting wires', J. Clarke: 'SQUID concepts and systems'. (orig.) With 10 tabs., 128 figs., 219 refs

Path Analysis Examining Self-Efficacy and Decision-Making Performance on a Simulated Baseball Task

Science.gov (United States)

Hepler, Teri J.; Feltz, Deborah L.

2012-01-01

The purpose of this study was to examine the relationship between decision-making self-efficacy and decision-making performance in sport. Undergraduate students (N = 78) performed 10 trials of a decision-making task in baseball. Self-efficacy was measured before performing each trial. Decision-making performance was assessed by decision speed and…

Dai Omega, a large solid angle axial focusing superconducting surface muon channel

International Nuclear Information System (INIS)

Miyadera, H.; Nagamine, K.; Shimomura, K.; Nishiyama, K.; Tanaka, H.; Fukuchi, K.; Makimura, S.; Ishida, K.

2003-01-01

An axial focusing surface muon channel, Dai Omega, was installed at KEK-MSL in the summer of 2001. Large aperture superconducting coils are utilized instead of quadrupole magnets. Dai Omega adopts an axial focusing beam path using symmetric magnetic fields from four coils. Computer simulations were performed on constructing Dai Omega, and the calculated solid angle acceptance of Dai Omega was larger than 1 sr at the optimum momentum. The momentum acceptance of Dai Omega was 6% FWHM. Dai Omega improved the solid angle acceptance by almost 20 times, in comparison with conventional muon channels. Beam tuning tests of Dai Omega have been carried out, and a beam intensity of 10 6 μ + /s was achieved at KEK-NML (500 MeV, 5 μA), which was almost comparable with that of RAL (800 MeV, 200 μA)

Flux penetration in a ferromagnetic/superconducting bilayer

Energy Technology Data Exchange (ETDEWEB)

Adamus, Z.; Cieplak, M.Z.; Abal' Oshev, A. [Polish Acad Sci, Inst Phys, PL-02668 Warsaw, (Poland); Konczykowski, M. [CEA/DSM/DRECAM, Laboratoire des Solides Irradies, F-91191 Gif Sur Yvette, (France); Konczykowski, M. [Ecole Polytech, CNRS - UMR 7642, F-91128 Palaiseau, (France); Cheng, X.M.; Zhu, L.Y.; Chien, C.L. [Johns Hopkins Univ, Dept Phys and Astron, Baltimore, MD 21218 (United States)

2007-07-01

An array of miniature Hall sensors is used to study the magnetic flux penetration in a ferromagnetic/superconducting bilayer consisting of Nb as a superconducting layer and Co/Pt multilayer with perpendicular magnetic anisotropy as a ferromagnetic layer, separated by an amorphous Si layer to avoid the proximity effect. It is found that the magnetic domains in the ferromagnetic layer create a large edge barrier in the superconducting layer which delays flux penetration. The smooth flux profiles observed in the absence of magnetic pinning change into terraced profiles in the presence of domains. (authors)

Theory of superconductivity

International Nuclear Information System (INIS)

Crisan, M.

1988-01-01

This book discusses the most important aspects of the theory. The phenomenological model is followed by the microscopic theory of superconductivity, in which modern formalism of the many-body theory is used to treat most important problems such as superconducting alloys, coexistence of superconductivity with the magnetic order, and superconductivity in quasi-one-dimensional systems. It concludes with a discussion on models for exotic and high temperature superconductivity. Its main aim is to review, as complete as possible, the theory of superconductivity from classical models and methods up to the 1987 results on high temperature superconductivity. Contents: Phenomenological Theory of Superconductivity; Microscopic Theory of Superconductivity; Theory of Superconducting Alloys; Superconductors in a Magnetic Field; Superconductivity and Magnetic Order; Superconductivity in Quasi-One-Dimensional Systems; and Non-Conventional Superconductivity

Applied superconductivity

CERN Document Server

Newhouse, Vernon L

1975-01-01

Applied Superconductivity, Volume II, is part of a two-volume series on applied superconductivity. The first volume dealt with electronic applications and radiation detection, and contains a chapter on liquid helium refrigeration. The present volume discusses magnets, electromechanical applications, accelerators, and microwave and rf devices. The book opens with a chapter on high-field superconducting magnets, covering applications and magnet design. Subsequent chapters discuss superconductive machinery such as superconductive bearings and motors; rf superconducting devices; and future prospec

Double-Play: Using Minor League Baseball to Apply Themes and Standards in Human Geography Courses

Science.gov (United States)

Zeitler, Ezra

2013-01-01

Growing student interest in sports provides geography teachers with a special opportunity to make connections between it and fundamental concepts in the discipline. This article examines the structure, arrangement, relationships, and distinctions among minor league baseball franchise locations, stadia, and team names, and presents examples of…

Overview of Superconductivity and Challenges in Applications

Science.gov (United States)

Flükiger, Rene

2012-01-01

Considerable progress has been achieved during the last few decades in the various fields of applied superconductivity, while the related low temperature technology has reached a high level. Magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR) are so far the most successful applications, with tens of thousands of units worldwide, but high potential can also be recognized in the energy sector, with high energy cables, transformers, motors, generators for wind turbines, fault current limiters and devices for magnetic energy storage. A large number of magnet and cable prototypes have been constructed, showing in all cases high reliability. Large projects involving the construction of magnets, solenoids as well as dipoles and quadrupoles are described in the present book. A very large project, the LHC, is currently in operation, demonstrating that superconductivity is a reliable technology, even in a device of unprecedented high complexity. A project of similar complexity is ITER, a fusion device that is presently under construction. This article starts with a brief historical introduction to superconductivity as a phenomenon, and some fundamental properties necessary for the understanding of the technical behavior of superconductors are described. The introduction of superconductivity in the industrial cycle faces many challenges, first for the properties of the base elements, e.g. the wires, tapes and thin films, then for the various applied devices, where a number of new difficulties had to be resolved. A variety of industrial applications in energy, medicine and communications are briefly presented, showing how superconductivity is now entering the market.

Contamination issues in superconducting cavity technology

International Nuclear Information System (INIS)

Kneisel, Peter

1997-01-01

The application of radio-frequency superconductivity technology in particle accelerator projects has become increasingly evident in recent years. Several large scale projects around the world are either completed or close to completion, such as CEBAF, HERA, TRISTAN and LEP. And superconducting cavity technology is seriously being considered for future applications in linear colliders (TESLA), high current proton accelerators (APT, spallation neutron sources), muon colliders and free electron lasers for industrial application. The reason for this multitude of activities are matured technology based on a better understanding of the phenomena encountered in superconducting cavities and the influence of improved material properties and contamination and quality control measures

1D-transport properties of single superconducting lead nanowires

DEFF Research Database (Denmark)

Michotte, S.; Mátéfi-Tempfli, Stefan; Piraux, L.

2003-01-01

of the nanowire is small enough to ensure a 1D superconducting regime in a wide temperature range below T. The non-zero resistance in the superconducting state and its variation caused by fluctuations of the superconducting order parameter were measured versus temperature, magnetic field, and applied DC current......We report on the transport properties of single superconducting lead nanowires grown by an electrodeposition technique, embedded in a nanoporous track-etched polymer membrane. The nanowires are granular, have uniform diameter of ̃40 nm and a very large aspect ratio (̃500). The diameter...

Analysis of an HTS coil for large scale superconducting magnetic energy storage

Energy Technology Data Exchange (ETDEWEB)

Lee, Ji Young; Lee, Se Yeon; Choi, Kyeong Dal; Park, Sang Ho; Hong, Gye Won; Kim, Sung Soo; Kim, Woo Seok [Korea Polytechnic University, Siheung (Korea, Republic of); Lee, Ji Kwang [Woosuk University, Wanju (Korea, Republic of)

2015-06-15

It has been well known that a toroid is the inevitable shape for a high temperature superconducting (HTS) coil as a component of a large scale superconducting magnetic energy storage system (SMES) because it is the best option to minimize a magnetic field intensity applied perpendicularly to the HTS wires. Even though a perfect toroid coil does not have a perpendicular magnetic field, for a practical toroid coil composed of many HTS pancake coils, some type of perpendicular magnetic field cannot be avoided, which is a major cause of degradation of the HTS wires. In order to suggest an optimum design solution for an HTS SMES system, we need an accurate, fast, and effective calculation for the magnetic field, mechanical stresses, and stored energy. As a calculation method for these criteria, a numerical calculation such as an finite element method (FEM) has usually been adopted. However, a 3-dimensional FEM can involve complicated calculation and can be relatively time consuming, which leads to very inefficient iterations for an optimal design process. In this paper, we suggested an intuitive and effective way to determine the maximum magnetic field intensity in the HTS coil by using an analytic and statistical calculation method. We were able to achieve a remarkable reduction of the calculation time by using this method. The calculation results using this method for sample model coils were compared with those obtained by conventional numerical method to verify the accuracy and availability of this proposed method. After the successful substitution of this calculation method for the proposed design program, a similar method of determining the maximum mechanical stress in the HTS coil will also be studied as a future work.

Analysis of an HTS coil for large scale superconducting magnetic energy storage

International Nuclear Information System (INIS)

Lee, Ji Young; Lee, Se Yeon; Choi, Kyeong Dal; Park, Sang Ho; Hong, Gye Won; Kim, Sung Soo; Kim, Woo Seok; Lee, Ji Kwang

2015-01-01

It has been well known that a toroid is the inevitable shape for a high temperature superconducting (HTS) coil as a component of a large scale superconducting magnetic energy storage system (SMES) because it is the best option to minimize a magnetic field intensity applied perpendicularly to the HTS wires. Even though a perfect toroid coil does not have a perpendicular magnetic field, for a practical toroid coil composed of many HTS pancake coils, some type of perpendicular magnetic field cannot be avoided, which is a major cause of degradation of the HTS wires. In order to suggest an optimum design solution for an HTS SMES system, we need an accurate, fast, and effective calculation for the magnetic field, mechanical stresses, and stored energy. As a calculation method for these criteria, a numerical calculation such as an finite element method (FEM) has usually been adopted. However, a 3-dimensional FEM can involve complicated calculation and can be relatively time consuming, which leads to very inefficient iterations for an optimal design process. In this paper, we suggested an intuitive and effective way to determine the maximum magnetic field intensity in the HTS coil by using an analytic and statistical calculation method. We were able to achieve a remarkable reduction of the calculation time by using this method. The calculation results using this method for sample model coils were compared with those obtained by conventional numerical method to verify the accuracy and availability of this proposed method. After the successful substitution of this calculation method for the proposed design program, a similar method of determining the maximum mechanical stress in the HTS coil will also be studied as a future work

Powering and Machine Protection of the Superconducting LHC Accelerator

CERN Document Server

Zerlauth, M

2004-01-01

A very large number of magnets, both superconducting and conventional copper conductor magnets, are installed in the LHC (Large Hadron Collider) for the guidance of the two proton beams around the circumference. In total, the LHC counts 1614 different electrical circuits with 1712 power converters for DC powering of the superconducting and normal conducting magnets. Besides the electrical circuits connecting main magnets for bending and focusing of the two counter-rotating beams, the demanding requirements on the quality of the magnetic fields require a large number of circuits for corrector magnets distributed around the circumference. In total, more than 10000 magnets will need to be connected to the power converters via a large inventory of electrical components such as normal conducting cables and tubes, energy extraction systems, current feedthroughs and superconducting busbars. Depending on the complexity and importance of these electrical circuits and their components, various systems will interact for...

Descriptive profile of hip rotation range of motion in elite tennis players and professional baseball pitchers.

Science.gov (United States)

Ellenbecker, Todd S; Ellenbecker, Gail A; Roetert, E Paul; Silva, Rogerio Teixeira; Keuter, Greg; Sperling, Fabio

2007-08-01

Repetitive loading to the hip joint in athletes has been reported as a factor in the development of degenerative joint disease and intra-articular injury. Little information is available on the bilateral symmetry of hip rotational measures in unilaterally dominant upper extremity athletes. Side-to-side differences in hip joint range of motion may be present because of asymmetrical loading in the lower extremities of elite tennis players and professional baseball pitchers. Cohort (cross-sectional) study (prevalence); Level of evidence, 1. Descriptive measures of hip internal and external rotation active range of motion were taken in the prone position of 64 male and 83 female elite tennis players and 101 male professional baseball pitchers using digital photos and computerized angle calculation software. Bilateral differences in active range of motion between the dominant and nondominant hip were compared using paired t tests and Bonferroni correction for hip internal, external, and total rotation range of motion. A Pearson correlation test was used to test the relationship between years of competition and hip rotation active range of motion. No significant bilateral difference (P > .005) was measured for mean hip internal or external rotation for the elite tennis players or the professional baseball pitchers. An analysis of the number of subjects in each group with a bilateral difference in hip rotation greater than 10 degrees identified 17% of the professional baseball pitchers with internal rotation differences and 42% with external rotation differences. Differences in the elite male tennis players occurred in only 15% of the players for internal rotation and 9% in external rotation. Female subjects had differences in 8% and 12% of the players for internal and external rotation, respectively. Statistical differences were found between the mean total arc of hip range of internal and external rotation in the elite tennis players with the dominant side being greater

Modeling of random geometric errors in superconducting magnets with applications to the CERN Large Hadron Collider

Directory of Open Access Journals (Sweden)

P. Ferracin

2000-12-01

Full Text Available Estimates of random field-shape errors induced by cable mispositioning in superconducting magnets are presented and specific applications to the Large Hadron Collider (LHC main dipoles and quadrupoles are extensively discussed. Numerical simulations obtained with Monte Carlo methods are compared to analytic estimates and are used to interpret the experimental data for the LHC dipole and quadrupole prototypes. The proposed approach can predict the effect of magnet tolerances on geometric components of random field-shape errors, and it is a useful tool to monitor the obtained tolerances during magnet production.

Survey of potential applications of superconducting suspensions

International Nuclear Information System (INIS)

Rao, D.K.; Bupara, S.S.

1993-01-01

The purpose of this report is to survey the recent developments in applying the bulk superconductors to mechanical applications. These applications, called superconducting suspensions, can be broadly divided into three groups - Passive Magnetic Bearings, Passive Superconducting Dampers and Active Superconducting Bearings. Basically, passive magnetic bearings utilize bulk superconductors to support a rotating shaft without contact while active superconducting bearings employ superconducting wires. Passive superconducting dampers, on the other hand, dissipate energy from a vibrating component. Over the past one year, dramatic improvements have been made in processing large-size specimens made of high grade bulk superconductors. As a result, they can meet the size requirements and load capacity requirements of many applications. With this size-scale up, one can utilize them in a wider number of applications than what was possible a few years back. At present several organizations have demonstrated the capability of passive magnetic bearings. The targeted applications include miniature cryoturboexpanders, cryoturbopumps, energy storage wheels and turbomolecular pumps. These demonstrations indicate that the passive magnetic bearings are closer to technology maturity. (orig.)

Superconductivity

International Nuclear Information System (INIS)

Caruana, C.M.

1988-01-01

Despite reports of new, high-temperature superconductive materials almost every day, participants at the First Congress on Superconductivity do not anticipate commercial applications with these materials soon. What many do envision is the discovery of superconducting materials that can function at much warmer, perhaps even room temperatures. Others hope superconductivity will usher in a new age of technology as semiconductors and transistors did. This article reviews what the speakers had to say at the four-day congress held in Houston last February. Several speakers voiced concern that the Reagan administration's apparent lack of interest in funding superconductivity research while other countries, notably Japan, continue to pour money into research and development could hamper America's international competitiveness

Superconducting magnets for toroidal fusion reactors

International Nuclear Information System (INIS)

Haubenreich, P.N.

1980-01-01

Fusion reactors will soon be employing superconducting magnets to confine plasma in which deuterium and tritium (D-T) are fused to produce usable energy. At present there is one small confinement experiment with superconducting toroidal field (TF) coils: Tokamak 7 (T-7), in the USSR, which operates at 4 T. By 1983, six different 2.5 x 3.5-m D-shaped coils from six manufacturers in four countries will be assembled in a toroidal array in the Large Coil Test Facility (LCTF) at Oak Ridge National Laboratory (ORNL) for testing at fields up to 8 T. Soon afterwards ELMO Bumpy Torus (EBT-P) will begin operation at Oak Ridge with superconducting TF coils. At the same time there will be tokamaks with superconducting TF coils 2 to 3 m in diameter in the USSR and France. Toroidal field strength in these machines will range from 6 to 9 T. NbTi and Nb 3 Sn, bath cooling and forced flow, cryostable and metastable - various designs are being tried in this period when this new application of superconductivity is growing and maturing

Handbook on superconductivity: the large-scale applications. Chapter IV. Stability

International Nuclear Information System (INIS)

Dresner, L.

1984-01-01

One way to cool a magnet is to immerse it in a bath of liquid helium. Boiling helium is a favorite because of helium's large latent heat of vaporization, but as in all boiling heat transfer, blanketing of the surface by vapor (film boiling) limits the attainable heat transfer. A second way to cool is with single-phase supercritical helium. To make the heat transfer high, helium in turbulent flow is forced through hollow conductors. A third way to cool is with He-II at atmospheric pressure. The He-II phase of helium, which remains liquid right down to absolute zero, has some remarkable properties that distinguish it from all other liquids, including the normal liquid phase of helium, He-I. These properties have excited great interest in He-II as a coolant for superconducting magnets. Each of these ways of cooling leads to a class of specialized problems that are discussed in detail. A somewhat different way to forestall quenches is to pot the conductor in a material that tightly confines it and to cool it indirectly by conduction to helium not directly in contact with it. The special problems of this approach are discussed as well

Superconducting magnets in the world of energy, especially in fusion power

International Nuclear Information System (INIS)

Komarek, P.

1976-01-01

Industrial applications of superconducting magnets are only feasible in the near future for superconducting monopolar machines and possible MHD generators. For superconducting synchronous machines, after the successful operation of machines in the MVA range, a new phase of basic investigations has started. Fundamental problems which could not be studied in the MVA machines, but which influence the design of large turbo-alternators, must now be investigated. Fusion power by magnetic confinement will probably be the largest field of application for superconducting magnets in the long run. The present research programmes require large superconducting magnets by the mid-1980s for the experimental reactors envisaged at that time. In addition to dc windings, pulse-operated superconducting windings are required in some systems, such as Tokamak. The high sensitivity of the overall plant efficiency and the active power demand of the pulsed windings require great efficiency from energy storage and transfer systems. Superconducting energy storage systems would be suitable for this, if transfer between inductances could be provided with sufficient efficiency. Basic experiments gave encouraging results. In power plant systems and electric machines an extremely high level of reliability and availability has been achieved. Less reliability will not be accepted for systems with superconducting magnets. This requires great efforts during the development work. (author)

Throwing-related injuries of the subscapularis in professional baseball players

Energy Technology Data Exchange (ETDEWEB)

Polster, Joshua M.; Ilaslan, Hakan; Subhas, Naveen [Cleveland Clinic, Imaging Institute, Cleveland, OH (United States); Lynch, T.S. [Columbia University Medical Center, Center for Shoulder, Elbow and Sports Medicine, New York, NY (United States); Bullen, Jennifer A. [Cleveland Clinic, Quantitative Health Sciences, Cleveland, OH (United States); Soloff, Lonnie [Cleveland Indians, Cleveland, OH (United States); Schickendantz, Mark S. [Cleveland Clinic, Orthopedic and Rheumatologic Institute, Cleveland, OH (United States)

2016-01-15

To describe the MR appearance of a series of throwing-related injuries to the subscapularis muscle-tendon complex among baseball players. A retrospective review of MR scans of the shoulder in players from 1 professional baseball organization over the course of 5 years was performed to identify cases with findings suggestive of subscapularis injury. These findings were graded and the medical record was reviewed to assess clinical findings, treatment, and follow-up. Preinjury baseline measurements of arm external rotation at 90 of abduction were compared to measurements from a noninjured cohort to evaluate whether this measure is a risk factor for injury. A total of 133 MR scans of the shoulder were evaluated. Eleven of the scans demonstrated signal changes suggesting subscapularis injury; 10 of these 11 patients had clinical findings supporting a diagnosis of throwing-related subscapularis strain. There were four grade 1, four grade 2, and two grade 3 injuries. All injuries occurred in the inferior half of the subscapularis at the myotendinous junction. Risk of subscapularis injury increased with lower levels of dominant arm external rotation (odds ratio, 1.12; 95 % CI, 1.07-1.21; p < 0.001). A threshold of dominant arm external rotation of <106 demonstrated sensitivity of 0.700 (95 % CI, 0.392-0.897) and specificity of 0.951 (95 % CI, 0.888-0.982) for subscapularis injury. Throwing-related subscapularis injuries occur in the inferior half of the muscle at the myotendinous junction. Our data suggest that there is an increased risk of these injuries with lower levels of dominant arm external rotation. (orig.)

Throwing-related injuries of the subscapularis in professional baseball players

International Nuclear Information System (INIS)

Polster, Joshua M.; Ilaslan, Hakan; Subhas, Naveen; Lynch, T.S.; Bullen, Jennifer A.; Soloff, Lonnie; Schickendantz, Mark S.

2016-01-01

To describe the MR appearance of a series of throwing-related injuries to the subscapularis muscle-tendon complex among baseball players. A retrospective review of MR scans of the shoulder in players from 1 professional baseball organization over the course of 5 years was performed to identify cases with findings suggestive of subscapularis injury. These findings were graded and the medical record was reviewed to assess clinical findings, treatment, and follow-up. Preinjury baseline measurements of arm external rotation at 90 of abduction were compared to measurements from a noninjured cohort to evaluate whether this measure is a risk factor for injury. A total of 133 MR scans of the shoulder were evaluated. Eleven of the scans demonstrated signal changes suggesting subscapularis injury; 10 of these 11 patients had clinical findings supporting a diagnosis of throwing-related subscapularis strain. There were four grade 1, four grade 2, and two grade 3 injuries. All injuries occurred in the inferior half of the subscapularis at the myotendinous junction. Risk of subscapularis injury increased with lower levels of dominant arm external rotation (odds ratio, 1.12; 95 % CI, 1.07-1.21; p < 0.001). A threshold of dominant arm external rotation of <106 demonstrated sensitivity of 0.700 (95 % CI, 0.392-0.897) and specificity of 0.951 (95 % CI, 0.888-0.982) for subscapularis injury. Throwing-related subscapularis injuries occur in the inferior half of the muscle at the myotendinous junction. Our data suggest that there is an increased risk of these injuries with lower levels of dominant arm external rotation. (orig.)

76 FR 37007 - Safety Zone; Stockton Ports Baseball Club Fourth of July Fireworks Display, Stockton, CA

Science.gov (United States)

2011-06-24

..., performance, design, or operation; test methods; sampling procedures; and related management systems practices...-AA00 Safety Zone; Stockton Ports Baseball Club Fourth of July Fireworks Display, Stockton, CA AGENCY... inspection or copying two locations: the Docket Management Facility (M-30), U.S. Department of Transportation...

Mechanical study of 20 MJ superconducting pulse coil

International Nuclear Information System (INIS)

Hattori, Yasuhide; Shimamoto, Susumu

1985-09-01

This paper describes calculation methods and computer codes of stress distribution in a circular-shaped superconducting pulsed coils. The stress problems of a large sized superconducting coil, for example, are discussed for 20 MJ pool-cooled pulse coil. Young's modulus of a stranded flat cable, low rigidity, is measured and evaluated. (author)

A superconducting focusing solenoid for the neutrino factory linear accelerator

International Nuclear Information System (INIS)

Green, Michael A.; Lebedev, V.; Strauss, B.P.

2001-01-01

The proposed linear Accelerator that accelerates muons from 190 MeV to 2.45 GeV will use superconducting solenoids for focusing the muon beam. The accelerator will use superconducting RF cavities. These cavities are very sensitive to stay magnetic field from the focusing magnets. Superconducting solenoids can produce large stray fields. This report describes the 201.25 MHz acceleration system for the neutrino factory. This report also describes a focusing solenoid that delivers almost no stray field to a neighboring superconducting RF cavity

Test equipment for a flywheel energy storage system using a magnetic bearing composed of superconducting coils and superconducting bulks

International Nuclear Information System (INIS)

Ogata, M; Matsue, H; Yamashita, T; Hasegawa, H; Nagashima, K; Maeda, T; Matsuoka, T; Mukoyama, S; Shimizu, H; Horiuchi, S

2016-01-01

Energy storage systems are necessary for renewable energy sources such as solar power in order to stabilize their output power, which fluctuates widely depending on the weather. Since ‘flywheel energy storage systems’ (FWSSs) do not use chemical reactions, they do not deteriorate due to charge or discharge. This is an advantage of FWSSs in applications for renewable energy plants. A conventional FWSS has capacity limitation because of the mechanical bearings used to support the flywheel. Therefore, we have designed a superconducting magnetic bearing composed of a superconducting coil stator and a superconducting bulk rotor in order to solve this problem, and have experimentally manufactured a large scale FWSS with a capacity of 100 kWh and an output power of 300 kW. The superconducting magnetic bearing can levitate 4 tons and enables the flywheel to rotate smoothly. A performance confirmation test will be started soon. An overview of the superconducting FWSS is presented in this paper. (paper)

Transient characteristics of current lead losses for the large scale high-temperature superconducting rotating machine

International Nuclear Information System (INIS)

Le, T. D.; Kim, J. H.; Park, S. I.; Kim, D. J.; Kim, H. M.; Lee, H. G.; Yoon, Y. S.; Jo, Y. S.; Yoon, K. Y.

2014-01-01

To minimize most heat loss of current lead for high-temperature superconducting (HTS) rotating machine, the choice of conductor properties and lead geometry - such as length, cross section, and cooling surface area - are one of the various significant factors must be selected. Therefore, an optimal lead for large scale of HTS rotating machine has presented before. Not let up with these trends, this paper continues to improve of diminishing heat loss for HTS part according to different model. It also determines the simplification conditions for an evaluation of the main flux flow loss and eddy current loss transient characteristics during charging and discharging period.

Method for obtaining large levitation pressure in superconducting magnetic bearings

Science.gov (United States)

Hull, John R.

1996-01-01

A method and apparatus for compressing magnetic flux to achieve high levitation pressures. Magnetic flux produced by a magnetic flux source travels through a gap between two high temperature superconducting material structures. The gap has a varying cross-sectional area to compress the magnetic flux, providing an increased magnetic field and correspondingly increased levitation force in the gap.

Powering and Machine Protection of the Superconducting LHC Accelerator

OpenAIRE

Zerlauth, M; Schmidt, R

2004-01-01

A very large number of magnets, both superconducting and conventional copper conductor magnets, are installed in the LHC (Large Hadron Collider) for the guidance of the two proton beams around the circumference. In total, the LHC counts 1614 different electrical circuits with 1712 power converters for DC powering of the superconducting and normal conducting magnets. Besides the electrical circuits connecting main magnets for bending and focusing of the two counter-rotating beams, the demandin...

Wire rope superconducting cable for diurnal load leveling SMES

International Nuclear Information System (INIS)

Costello, G.A.

1980-01-01

The design of a wire rope cable for a superconducting magnetic energy storage (SMES) unit is discussed. The superconducting wires in the rope permit the passage of large currents in the relatively small conductors of the windings and hence cause large electromagnetic forces to act on the rope. The diameter of the rope, from a strength point of view, can be considerably reduced by supporting the rope at various points along its length

MICROSTRUCTURE OF SUPERCONDUCTING MGB(2).

Energy Technology Data Exchange (ETDEWEB)

ZHU,Y.; LI,Q.; WU,L.; VOLKOV,V.; GU,G.; MOODENBAUGH,A.R.

2001-07-12

Recently, Akimitsu and co-workers [1] discovered superconductivity at 39 K in the intermetallic compound MgB{sub 2}. This discovery provides a new perspective on the mechanism for superconductivity. More specifically, it opens up possibilities for investigation of structure/properties in a new class of materials. With the exceptions of the cuprate and C{sub 60} families of compounds, MgB{sub 2} possesses the highest superconducting transition temperature T{sub c}. Its superconductivity appears to follow the BCS theory, apparently being mediated by electron-phonon coupling. The coherence length of MgB{sub 2} is reported to be longer than that of the cuprates [2]. In contrast to the cuprates, grain boundaries are strongly coupled and current density is determined by flux pinning [2,3]. Presently, samples of MgB{sub 2} commonly display inhomogeneity and porosity on the nanoscale, and are untextured. In spite of these obstacles, magnetization and transport measurements show that polycrystalline samples may carry large current densities circulating across many grains [3,4]. Very high values of critical current densities and critical fields have been recently observed in thin films [5,6]. These attributes suggest possible large scale and electronic applications. The underlying microstructure can be intriguing, both in terms of basic science and in applied areas. Subsequent to the discovery, many papers were published [1-13], most dealing with synthesis, physical properties, and theory. There have yet been few studies of microstructure and structural defects [11, 14]. A thorough understanding of practical superconducting properties can only be developed after an understanding of microstructure is gained. In this work we review transmission electron microscopy (TEM) studies of sintered MgB{sub 2} pellets [14]. Structural defects, including second phase particles, dislocations, stacking faults, and grain boundaries, are analyzed using electron diffraction, electron

Florida State University superconducting linac

International Nuclear Information System (INIS)

Myers, E.G.; Fox, J.D.; Frawley, A.D.; Allen, P.; Faragasso, J.; Smith, D.; Wright, L.

1988-01-01

As early as the fall of 1977 it was decided that the future research needs of their nuclear structure laboratory required an increase in energy capability to at least 8 MeV per nucleon for the lighter ions, and that these needs could be met by the installation of a 17 MV tandem Van de Graaff accelerator. The chief problem with this proposal was the high cost. It became apparent that a far less expensive option was to construct a linear accelerator to boost the energy from their existing 9 MV tandem. The options open to them among linac boosters were well represented by the room temperature linac at Heidelberg and the superconducting Stony Brook and Argonne systems. By the Spring of 1979 it had been decided that both capital cost and electric power requirements favored a superconducting system. As regards the two superconducting resonator technologies - the Argonne niobium-copper or the Caltech-Stony Brook lead plated copper - the Argonne resonators, though more expensive to construct, had the advantages of more boost per resonator, greater durability of the superconducting surface and less stringent beam bunching requirements. In 1980 pilot funding from the State of Florida enabled the construction of a building addition to house the linac and a new target area, and the setting up of a small, three resonator, test booster. Major funding by the NSF for the laboratory upgrade started in 1984. With these funds they purchased their present helium liquefaction and transfer system and constructed three large cryostats, each housing four Argonne beta = 0.105 resonators and two superconducting solenoids. The last large cryostat was completed and installed on-line early this year and the linac was dedicated on March 20. Nuclear physics experiments using the whole linac began in early June. 4 references, 6 figures, 1 table

Development of the Curriculum and Instructional Model for Learning the Tactical Awareness by the Each Role in the Baseball Game in the Elementary School

OpenAIRE

中井, 隆司; 宗野, 伸哉; 川島, 弘美

2006-01-01

The purpose of this study was to develop the curriculum and instructional model for learning the tactical awareness by the each role in the baseball game in the elemetary school. This baseball game' s practice composed three task games, the drill game and the teaching process for learning "tactical awareness". For analyzing the learning process and the products, four students were selected by the throwing ability. In this teaching unit, the learning process and the products were measured in t...

General Atomic's superconducting toroidal field coil concept

International Nuclear Information System (INIS)

Alcorn, J.; Purcell, J.

1978-01-01

General Atomic's concept for a superconducting toroidal field coil is presented. The concept is generic for large tokamak devices, while a specific design is indicated for a 3.8 meter (major radius) ignition/burn machine. The concept utilizes bath cooled NbTi conductor to generate a peak field of 10 tesla at 4.2 K. The design is simple and straightforward, requires a minimum of developmental effort, and draws extensively upon the perspective of past experience in the design and construction of large superconducting magnets for high energy physics. Thus, the primary emphasis is upon economy, reliability, and expeditious construction scheduling. (author)

Test Station for Magnetization Measurements on Large Quantities of Superconducting Strands

CERN Document Server

Le Naour, S; Billan, J; Genest, J

2001-01-01

In the superconducting main magnets of the Large Hadron Collider (LHC), persistent currents in the superconductor determine the field quality at injection field. For this reason it is necessary to check the magnetization of the cable strands during their production. During four years, this requires measurements of the width of the strand magnetization hysteresis loop at 0.5 T, 1.9 K, at a rate of up to eight samples per day. This paper describes the design, construction and the first results of a magnetization test station built for this purpose. The samples are cooled in a cryostat, with a 2-m long elliptic tail. This tail is inserted in a normal conducting dipole magnet with a field between ± 1.5 T. Racetrack pick-up coils, integrated in the cryostat, detect the voltage due to flux change, which is then integrated numerically. The sample holder can contain eight strand samples, each 20 cm long. The test station operates in two modes: either the sample is fixed while the external field is changed, or the sa...

Large superconducting detector magnets with ultra thin coils for use in high energy accelerators and storage rings

International Nuclear Information System (INIS)

Green, M.A.

1977-08-01

The development of a new class of large superconducting solenoid magnets is described. High energy physics on colliding beam machines sometimes require the use of thin coil solenoid magnets. The development of these magnets has proceeded with the substitution of light materials for heavy materials and by increasing the current density in the coils. The Lawrence Berkeley Laboratory has developed a radical approach to the problem by having the coil operate at very high current densities. This approach and its implications are described in detail

Variable temperature superconducting microscope

Science.gov (United States)

Cheng, Bo; Yeh, W. J.

2000-03-01

We have developed and tested a promising type of superconducting quantum interference device (SQUID) microscope, which can be used to detect vortex motion and can operate in magnetic fields over a large temperature range. The system utilizes a single-loop coupling transformer, consisting of a patterned high Tc superconducting thin film. At one end of the transformer, a 20 μm diam detecting loop is placed close to the sample. At the other end, a large loop is coupled to a NbTi coil, which is connected to a low Tc SQUID sensor. Transformers in a variety of sizes have been tested and calibrated. The results show that the system is capable of detecting the motion of a single vortex. We have used the microscope to study the behavior of moving vortices at various positions in a YBa2Cu3O7 thin film bridge.

Research and development of superconductivity for energy technology in electrotechnical laboratory

International Nuclear Information System (INIS)

Koyama, K.

1984-01-01

Superconductivity is a physical effect wherein the electrical resistivity disappears at cryogenic temperatures. Superconductivity has the advantage of following large current densities and high magnetic fields, which are stable and homogeneous. There are many applications of superconductivity which take advantage of these merits. It is of special importance to apply superconductors to alternative energy and energy saving technology. This paper presents briefly some of the research and development efforts to apply superconductivity to energy technology in the Electrotechnical Laboratory

Birth order and risk taking in athletics: a meta-analysis and study of major league baseball.

Science.gov (United States)

Sulloway, Frank J; Zweigenhaft, Richard L

2010-11-01

According to expectations derived from evolutionary theory, younger siblings are more likely than older siblings to participate in high-risk activities. The authors test this hypothesis by conducting a meta-analysis of 24 previous studies involving birth order and participation in dangerous sports. The odds of laterborns engaging in such activities were 1.48 times greater than for firstborns (N = 8,340). The authors also analyze performance data on 700 brothers who played major league baseball. Consistent with their greater expected propensity for risk taking, younger brothers were 10.6 times more likely to attempt the high-risk activity of base stealing and 3.2 times more likely to steal bases successfully (odds ratios). In addition, younger brothers were significantly superior to older brothers in overall batting success, including two measures associated with risk taking. As expected, significant heterogeneity among various performance measures for major league baseball players indicated that older and younger brothers excelled in different aspects of the game.

Large-area NbN superconducting nanowire avalanche photon detectors with saturated detection efficiency

Science.gov (United States)

Murphy, Ryan P.; Grein, Matthew E.; Gudmundsen, Theodore J.; McCaughan, Adam; Najafi, Faraz; Berggren, Karl K.; Marsili, Francesco; Dauler, Eric A.

2015-05-01

Superconducting circuits comprising SNSPDs placed in parallel—superconducting nanowire avalanche photodetectors, or SNAPs—have previously been demonstrated to improve the output signal-to-noise ratio (SNR) by increasing the critical current. In this work, we employ a 2-SNAP superconducting circuit with narrow (40 nm) niobium nitride (NbN) nanowires to improve the system detection efficiency to near-IR photons while maintaining high SNR. Additionally, while previous 2-SNAP demonstrations have added external choke inductance to stabilize the avalanching photocurrent, we show that the external inductance can be entirely folded into the active area by cascading 2-SNAP devices in series to produce a greatly increased active area. We fabricated series-2-SNAP (s2-SNAP) circuits with a nanowire length of 20 μm with cascades of 2-SNAPs providing the choke inductance necessary for SNAP operation. We observed that (1) the detection efficiency saturated at high bias currents, and (2) the 40 nm 2-SNAP circuit critical current was approximately twice that for a 40 nm non-SNAP configuration.

Superconductivity in the background of disordered flux state of spins

International Nuclear Information System (INIS)

Feng Shiping; Guo Rui; Han Fei

1992-01-01

The phase diagram of the copper oxide materials with the antiferromagnetic and the superconducting properties as a function of doping δ is obtained in the framework of the t-J model by using the Schwinger boson-slave fermion theory. The results show that the spiral order of spins competes and coexists with superconductivity for small doping δ. For large doping δ, superconductivity appears, which may be caused by the occurrence of a disordered flux state of spins. The phase diagram suggests a strong relationship between antiferromagnetism and superconductivity. (orig.)

Investigation of superconducting properties of nanowires prepared by template synthesis

DEFF Research Database (Denmark)

Michotte, S.; Mátéfi-Tempfli, Stefan; Piraux, L.

2003-01-01

of the nanowires is small enough to ensure a one-dimensional superconducting regime in a wide temperature range below T. The non-zero resistance in the superconducting state and its variation caused by fluctuations of the superconducting order parameter were measured versus temperature, magnetic field, and applied......We report on the transport properties of single superconducting lead nanowires grown by an electrodeposition technique, embedded in a nanoporous track-etched polymer membrane. The nanowires are granular, have a uniform diameter of ∼40 nm and a very large aspect ratio (∼500). The diameter...

A scanning Auger electron spectrometer for internal surface analysis of Large Electron Positron 2 superconducting radio-frequency cavities

Science.gov (United States)

Benvenuti, C.; Cosso, R.; Genest, J.; Hauer, M.; Lacarrère, D.; Rijllart, A.; Saban, R.

1996-08-01

A computer-controlled surface analysis instrument, incorporating static Auger electron spectroscopy, scanning Auger mapping, and secondary electron imaging, has been designed and built at CERN to study and characterize the inner surface of superconducting radio-frequency cavities to be installed in the Large Electron Positron collider. A detailed description of the instrument, including the analytical head, the control system, and the vacuum system is presented. Some recent results obtained from the cavities provide examples of the instrument's capabilities.

Effectiveness of Manual Therapy and Stretching for Baseball Players With Shoulder Range of Motion Deficits.

Science.gov (United States)

Bailey, Lane B; Thigpen, Charles A; Hawkins, Richard J; Beattie, Paul F; Shanley, Ellen

Baseball players displaying deficits in shoulder range of motion (ROM) are at increased risk of arm injury. Currently, there is a lack of consensus regarding the best available treatment options to restore shoulder ROM. Instrumented manual therapy with self-stretching will result in clinically significant deficit reductions when compared with self-stretching alone. Controlled laboratory study. Shoulder ROM and humeral torsion were assessed in 60 active baseball players (mean age, 19 ± 2 years) with ROM deficits (nondominant - dominant, ≥15°). Athletes were randomly assigned to receive a single treatment of instrumented manual therapy plus self-stretching (n = 30) or self-stretching only (n = 30). Deficits in internal rotation, horizontal adduction, and total arc of motion were compared between groups immediately before and after a single treatment session. Treatment effectiveness was determined by mean comparison data, and a number-needed-to-treat (NNT) analysis was used for assessing the presence of ROM risk factors. Prior to intervention, players displayed significant ( P < 0.001) dominant-sided deficits in internal rotation (-26°), total arc of motion (-18°), and horizontal adduction (-17°). After the intervention, both groups displayed significant improvements in ROM, with the instrumented manual therapy plus self-stretching group displaying greater increases in internal rotation (+5°, P = 0.010), total arc of motion (+6°, P = 0.010), and horizontal adduction (+7°, P = 0.004) compared with self-stretching alone. For horizontal adduction deficits, the added use of instrumented manual therapy with self-stretching decreased the NNT to 2.2 (95% CI, 2.1-2.4; P = 0.010). Instrumented manual therapy with self-stretching significantly reduces ROM risk factors in baseball players with motion deficits when compared with stretching alone. The added benefits of manual therapy may help to reduce ROM deficits in clinical scenarios where stretching alone is

Electromagnetic Design Study for a Large Bore 15T Superconducting Dipole Magnet

CERN Document Server

Schwerg, N; Devred, Arnaud; Henke, H

2005-01-01

In the framework of research and development (R&D) activities at CERN the Next European Dipole (NED) program is one which is to the development of a high-field dipole magnet using Nb_3Sn superconductors. Part of the NED activities is a design study of different possible dipole configurations which is shared amongst the collaborating institutes. This thesis covers the electromagnetic design study of an 88 mm large bore superconducting 15 T dipole magnet with a coil cross section in cos-theta-layer design. Based on analytically describable geometries the sources of multipole errors are studied and elementary estimations of the magnet are carried out, e.g., the required amount of superconductors or the influence of the iron yoke thickness on the field quality. The magnet cross section for NED is optimized by means of the CERN field computation program ROXIE. The preliminary NED design serves as starting point for the coil cross section optimization with respect to field quality and a radial positioning of th...

Development of high field superconducting magnet

International Nuclear Information System (INIS)

Irie, Fujio; Takeo, Masakatsu.

1986-01-01

Recently, in connection with nuclear fusion research, the development of high field superconducting magnets showed rapid progress. The development of high field magnets of 15 T class by the techniques of winding after heat treatment has been continued in various places, as these techniques are suitable to make large magnets. In 1985, Kyushu University attained the record of 15.5 T. However in high field magnets, there are many problems peculiar to them, and the basic research related to those is demanded. In this report, these general problems, the experience of the design and manufacture in Kyushu University and the related problems are described. The superconducting magnet installed in the Superconducting Magnet Research Center of Kyushu University attained the record of 15.5 T for the first time in March, 1985. In superconducting magnets, very difficult problem must be solved since superconductivity, heat and mechanical force are inter related. The problems of the wire materials for high field, the scale of high field magnets, the condition limiting mean current density, and the development of high field magnets in Kyushu University are described. (Kako, I.)

Interface-Induced Zeeman-Protected Superconductivity in Ultrathin Crystalline Lead Films

Science.gov (United States)

Liu, Yi; Wang, Ziqiao; Zhang, Xuefeng; Liu, Chaofei; Liu, Yongjie; Zhou, Zhimou; Wang, Junfeng; Wang, Qingyan; Liu, Yanzhao; Xi, Chuanying; Tian, Mingliang; Liu, Haiwen; Feng, Ji; Xie, X. C.; Wang, Jian

2018-04-01

Two-dimensional (2D) superconducting systems are of great importance for exploring exotic quantum physics. The recent development of fabrication techniques has stimulated studies of high-quality single-crystalline 2D superconductors, where intrinsic properties give rise to unprecedented physical phenomena. Here, we report the observation of Zeeman-type spin-orbit interaction protected superconductivity (Zeeman-protected superconductivity) in 4-monolayer (ML) to 6-ML crystalline Pb films grown on striped incommensurate Pb layers on Si(111) substrates by molecular beam epitaxy. An anomalously large in-plane critical field far beyond the Pauli limit is detected, which can be attributed to the Zeeman-protected superconductivity due to the in-plane inversion symmetry breaking at the interface. Our work demonstrates that, in superconducting heterostructures, the interface can induce Zeeman-type spin-orbit interactions and modulate the superconductivity.

Comparison of crossover and jab step start techniques for base stealing in baseball.

Science.gov (United States)

Miyanishi, Tomohisa; Endo, So; Nagahara, Ryu

2017-11-01

Base stealing is an important tactic for increasing the chance of scoring in baseball. This study aimed to compare the crossover step (CS) and jab step (JS) starts for base stealing start performance and to clarify the differences between CS and JS starts in terms of three-dimensional lower extremity joint kinetics. Twelve male baseball players performed CS and JS starts, during which their motion and the force they applied to the ground were simultaneously recorded using a motion-capture system and two force platforms. The results showed that the normalised average forward external power, the average forward-backward force exerted by the left leg, and the forward velocities of the whole body centre of gravity generated by both legs and the left leg were significantly higher for the JS start than for the CS start. Moreover, the positive work done by hip extension during the left leg push-off was two-times greater for the JS start than the CS start. In conclusion, this study has demonstrated that the jab step start may be the better technique for a base stealing start and that greater positive work produced by left hip extension is probably responsible for producing its larger forward ground reaction force.

Analysis of Mechanical Stresses/Strains in Superconducting Wire

Science.gov (United States)

Barry, Matthew; Chen, Jingping; Zhai, Yuhu

2016-10-01

The optimization of superconducting magnet performance and development of high-field superconducting magnets will greatly impact the next generation of fusion devices. A successful magnet development, however, relies deeply on the understanding of superconducting materials. Among the numerous factors that impact a superconductor's performance, mechanical stress is the most important because of the extreme operation temperature and large electromagnetic forces. In this study, mechanical theory is used to calculate the stresses/strains in typical superconducting strands, which consist of a stabilizer, a barrier, a matrix and superconducting filaments. Both thermal loads and mechanical loads are included in the analysis to simulate operation conditions. Because this model simulates the typical architecture of major superconducting materials, such as Nb3Sn, MgB2, Bi-2212 etc., it provides a good overall picture for us to understand the behavior of these superconductors in terms of thermal and mechanical loads. This work was supported in part by the U.S. Department of Energy, Office of Science, Office of Workforce Development for Teachers and Scientists (WDTS) under the Science Undergraduate Laboratory Internship (SULI) program.

Interface superconductivity

Energy Technology Data Exchange (ETDEWEB)

Gariglio, S., E-mail: stefano.gariglio@unige.ch [DQMP, Université de Genève, 24 Quai E.-Ansermet, CH-1211 Genève (Switzerland); Gabay, M. [Laboratoire de Physique des Solides, Bat 510, Université Paris-Sud 11, Centre d’Orsay, 91405 Orsay Cedex (France); Mannhart, J. [Max Planck Institute for Solid State Research, 70569 Stuttgart (Germany); Triscone, J.-M. [DQMP, Université de Genève, 24 Quai E.-Ansermet, CH-1211 Genève (Switzerland)

2015-07-15

Highlights: • We discuss interfacial superconductivity, a field boosted by the discovery of the superconducting interface between LaAlO. • This system allows the electric field control and the on/off switching of the superconducting state. • We compare superconductivity at the interface and in bulk doped SrTiO. • We discuss the role of the interfacially induced Rashba type spin–orbit. • We briefly discuss superconductivity in cuprates, in electrical double layer transistor field effect experiments. • Recent observations of a high T{sub c} in a monolayer of FeSe deposited on SrTiO{sub 3} are presented. - Abstract: Low dimensional superconducting systems have been the subject of numerous studies for many years. In this article, we focus our attention on interfacial superconductivity, a field that has been boosted by the discovery of superconductivity at the interface between the two band insulators LaAlO{sub 3} and SrTiO{sub 3}. We explore the properties of this amazing system that allows the electric field control and on/off switching of superconductivity. We discuss the similarities and differences between bulk doped SrTiO{sub 3} and the interface system and the possible role of the interfacially induced Rashba type spin–orbit. We also, more briefly, discuss interface superconductivity in cuprates, in electrical double layer transistor field effect experiments, and the recent observation of a high T{sub c} in a monolayer of FeSe deposited on SrTiO{sub 3}.

Design of a large superconducting spectrometer magnet

International Nuclear Information System (INIS)

Shintomi, T.; Makida, Y.; Mito, T.; Yamanoi, Y.; Hashimito, O.; Nagae, T.

1989-04-01

The superconducting spectrometer magnet for nuclear physics experiments has been under construction by Institute for Nuclear Study, University of Tokyo with collaboration from KEK. The magnet has a sector type coil. The magnetic field is 3 T with the magnet gap of 50 cm and the stored energy is 11.8 MJ. The easy operation and maintenance are taken into consideration in addition to usual design concept. Three dimensional magnetic field calculation and the stress analysis have been performed. The code 'QUENCH' was applied to decide the operation current and to check the safety of the coil. As a result, the current of 500 A was selected. The heat leaks were checked and estimated less than 2 W at 4 K. A small refrigerator is to be used for thermal insulations at 80 and 20 K. (author)

Superconducting coil and method of stress management in a superconducting coil

Science.gov (United States)

McIntyre, Peter M.; Shen, Weijun; Diaczenko, Nick; Gross, Dan A.

1999-01-01

A superconducting coil (12) having a plurality of superconducting layers (18) is provided. Each superconducting layer (18) may have at least one superconducting element (20) which produces an operational load. An outer support structure (24) may be disposed outwardly from the plurality of layers (18). A load transfer system (22) may be coupled between at least one of the superconducting elements (20) and the outer support structure (24). The load transfer system (22) may include a support matrix structure (30) operable to transfer the operational load from the superconducting element (20) directly to the outer support structure (24). A shear release layer (40) may be disposed, in part, between the superconducting element (20) and the support matrix structure (30) for relieving a shear stress between the superconducting element (20) and the support matrix structure (30). A compliant layer (42) may also be disposed, in part, between the superconducting element (20) and the support matrix structure (30) for relieving a compressive stress on the superconducting element (20).

How Major League Baseball Clubs Have Commercialized Their Investment in Japanese Top Stars

OpenAIRE

Isao Okada; Stephen A. Greyser

2013-01-01

When a Major League Baseball club signs a Japanese star player, it obviously tries to commercialize its investment in the player. The initial focus is on home attendance (ticket sales) and television audiences, plus merchandise sales. These elements are similar to those considered for any high-performing players. However, for Japanese stars, there is also the potential to attract significant fandom from the local Japanese community. This represents an opportunity for truly incremental local r...

Development and status of superconducting SR-ring

International Nuclear Information System (INIS)

Toyota, Eijiro; Tomimasu, Takio.

1991-01-01

Recently, attention has been paid to synchrotron radiation as a powerful tool for material science research, and for the most advanced research, stronger beam is sought for, therefore, large scale synchrotron radiation source facilities are going to be constructed. In contrast with the move toward large scale like this, effort is exerted to reduce the size by using superconductivity and to utilize for industries. Especially Japan precedes most in this field, and has already succeeded in the beam generation. This move to reduce size and pursue economic efficiency is noteworthy as that of supplementing the trend to large scale on the other hand, and its outline is explained. Synchrotron radiation means the strong beam emitted in tangential direction when the electrons or positrons moving at the velocity close to the velocity of light are bent in a magnetic field. The device which stably generates synchrotron radiation is an electron storage ring. The features of synchrotron radiation are explained. The history of synchrotron radiation research, the trend of development of superconducting synchrotron radiation ring, the actual examples of superconducting SR rings and their problems are described. (K.I.)

Determination of AC Characteristics of Superconducting Dipole Magnets in the Large Hadron Collider Based on Experimental Results and Simulations

CERN Document Server

Ambjørndalen, Sara; Verweij, Arjan

The Large Hadron Collider (LHC) utilizes high-field superconducting Main Dipole Magnets that bend the trajectory of the beam. The LHC ring is electrically divided into eight octants, each allocating a 7 km chain of 154 Main Dipole Magnets. Dedicated de- tection and protection systems prevent irreversible magnet damage caused by quenches. Quench is a local transition from the superconducting to the normal conducting state. Triggering of such systems, along with other failure scenarios, result in fast transient phenomena. In order to analyze the consequence of such electrical transients and failures in the dipole chain, one needs a circuit model that is validated against measurements. Currently, there exists an equivalent circuit of the Main Dipole Magnet resolved at an aperture level. Each aperture model takes into account the dynamic effects occurring in the magnets, trough a lossy-inductance model and parasitic capacitances to ground. At low frequencies the Main Dipole Magnet behaves as a linear inductor. Ca...

PREFACE PASREG: The 7th International Workshop on the Processing and Applications of Superconducting (RE)BCO Large Grain Materials (Washington DC, 29-31 July 2010) PASREG: The 7th International Workshop on the Processing and Applications of Superconducting (RE)BCO Large Grain Materials (Washington DC, 29-31 July 2010)

Science.gov (United States)

Freyhardt, Herbert; Cardwell, David; Strasik, Mike

2010-12-01

Large grain, (RE)BCO bulk superconductors fabricated by top seeded melt growth (TSMG) are able to generate large magnetic fields compared to conventional, iron-based permanent magnets. Following 20 years of development, these materials are now beginning to realize their considerable potential for a variety of engineering applications such as magnetic separators, flywheel energy storage and magnetic bearings. MgB2 has also continued to emerge as a potentially important bulk superconducting material for engineering applications below 20 K due to its lack of granularity and the ease with which complex shapes of this material can be fabricated. This issue of Superconductor Science and Technology contains a selection of papers presented at the 7th International Workshop on the Processing and Applications of Superconducting (RE)BCO Large Grain Materials, including MgB2, held 29th-31sy July 2010 at the Omni Shoreham Hotel, Washington DC, USA, to report progress made in this field in the previous three year period. The workshop followed those held previously in Cambridge, UK (1997), Morioka, Japan (1999), Seattle, USA (2001), Jena, Germany (2003), Tokyo, Japan (2005) and again in Cambridge, UK (2007). The scope of the seventh PASREG workshop was extended to include processing and characterization aspects of the broader spectrum of bulk high temperature superconducting (HTS) materials, including melt-cast Bi-HTS and bulk MgB2, recent developments in the field and innovative applications of bulk HTS. A total of 38 papers were presented at this workshop, of which 30 were presented in oral form and 8 were presented as posters. The organizers wish to acknowledge the efforts of Sue Butler of the University of Houston for her local organization of the workshop. The eighth PASREG workshop will be held in Taiwan in the summer of 2012.

Superconductivity

International Nuclear Information System (INIS)

Kakani, S.L.; Kakani, Shubhra

2007-01-01

The monograph provides readable introduction to the basics of superconductivity for beginners and experimentalists. For theorists, the monograph provides nice and brief description of the broad spectrum of experimental properties, theoretical concepts with all details, which theorists should learn, and provides a sound basis for students interested in studying superconducting theory at the microscopic level. Special chapter on the theory of high-temperature superconductivity in cuprates is devoted

Detection of Resistive Transitions in LHC Superconducting Components

CERN Document Server

Denz, R

2001-01-01

The LHC has entered the construction phase. It will incorporate a large number of superconducting components like magnets, current leads and busbars. All these components require protection means in case of a transition from the superconducting to the resistive state, the so-called quench. Key elements in the protection system are electronic quench detectors, which have to be able to identify a quench in any state of the powering cycle of the accelerator. According to the different properties and characteristics of the superconducting elements and circuits, a set of quench detectors adapted to their specific tasks has been developed.

US superconducting magnet data base assessment for INTOR

International Nuclear Information System (INIS)

Schultz, J.H.; Montgomery, D.B.

1984-01-01

Because of its size, performance requirements and exposure to neutron and gamma irradiation, the superconducting magnet system for INTOR would represent a significant advance in superconducting magnet technology. US programs such as LCP, MFTF-B and others provide a significant data base for the INTOR application. The assessment of the adequacy of the US data base for the INTOR magnets is largely generic, and applies to the superconducting magnet systems for other magnetic confinement fusion reactors. Assessments of the data base generated by other national magnet technology programs are being prepared by the other INTOR participants

Interface-Induced Zeeman-Protected Superconductivity in Ultrathin Crystalline Lead Films

Directory of Open Access Journals (Sweden)

Yi Liu

2018-04-01

Full Text Available Two-dimensional (2D superconducting systems are of great importance for exploring exotic quantum physics. The recent development of fabrication techniques has stimulated studies of high-quality single-crystalline 2D superconductors, where intrinsic properties give rise to unprecedented physical phenomena. Here, we report the observation of Zeeman-type spin-orbit interaction protected superconductivity (Zeeman-protected superconductivity in 4-monolayer (ML to 6-ML crystalline Pb films grown on striped incommensurate Pb layers on Si(111 substrates by molecular beam epitaxy. An anomalously large in-plane critical field far beyond the Pauli limit is detected, which can be attributed to the Zeeman-protected superconductivity due to the in-plane inversion symmetry breaking at the interface. Our work demonstrates that, in superconducting heterostructures, the interface can induce Zeeman-type spin-orbit interactions and modulate the superconductivity.

13th European Conference on Applied Superconductivity

CERN Document Server

2017-01-01

EUCAS is a worldwide forum for scientists and engineers, and provides an ideal platform to share knowledge and the most recent advances in all areas of applied superconductivity: from large-scale applications to miniature electronics devices, with a traditional focus on advanced materials and conductors. The broad scope is at the same time a challenge and an opportunity to foster novel, inter-disciplinary approaches and promote cross-fertilization among the various fields of applied superconductivity.

Conceptual study of superconducting urban area power systems

International Nuclear Information System (INIS)

Noe, Mathias; Gold-acker, Wilfried; Bach, Robert; Prusseit, Werner; Willen, Dag; Poelchau, Juri; Linke, Christian

2010-01-01

Efficient transmission, distribution and usage of electricity are fundamental requirements for providing citizens, societies and economies with essential energy resources. It will be a major future challenge to integrate more sustainable generation resources, to meet growing electricity demand and to renew electricity networks. Research and development on superconducting equipment and components have an important role to play in addressing these challenges. Up to now, most studies on superconducting applications in power systems have been concentrated on the application of specific devices like for example cables and current limiters. In contrast to this, the main focus of our study is to show the consequence of a large scale integration of superconducting power equipment in distribution level urban power systems. Specific objectives are to summarize the state-of-the-art of superconducting power equipment including cooling systems and to compare the superconducting power system with respect to energy and economic efficiency with conventional solutions. Several scenarios were considered starting from the replacement of an existing distribution level sub-grid up to a full superconducting urban area distribution level power system. One major result is that a full superconducting urban area distribution level power system could be cost competitive with existing solutions in the future. In addition to that, superconducting power systems offer higher energy efficiency as well as a number of technical advantages like lower voltage drops and improved stability.

Comparing the Immediate Effects of a Total Motion Release Warm-up and a Dynamic Warm-up Protocol on the Dominant Shoulder in Baseball Athletes.

Science.gov (United States)

Gamma, Stephen C; Baker, Russell; May, James; Seegmiller, Jeff G; Nasypany, Alan; Iorio, Steven M

2018-04-10

Gamma, SC, Baker, R, May, J, Seegmiller, JG, Nasypany, A, and Iorio, SM. Comparing the immediate effects of a total motion release warm-up and a dynamic warm-up protocol on the dominant shoulder in baseball athletes. J Strength Cond Res XX(X): 000-000, 2017-A decrease in total range of motion (ROM) of the dominant shoulder may predispose baseball athletes to increased shoulder injury risk; the most effective technique for improving ROM is unknown. The purpose of this study was to compare the immediate effects of Total Motion Release (TMR) to a generic dynamic warm-up program in baseball athletes. Baseball athletes (n = 20) were randomly assigned to an intervention group: TMR group (TMRG; n = 10) or traditional warm-up group (TWG; n = 10). Shoulder ROM measurements were recorded for internal rotation (IR) and external rotation (ER), the intervention was applied, and postmeasurements were recorded. Each group then received the other intervention and postmeasurements were again recorded. The time main effect (p ≤ 0.001) and the time × group interaction effect were significant (p ≤ 0.001) for IR and ER. Post hoc analysis revealed that TMR produced significant increases in mean IR (p ≤ 0.005, d = 1.52) and ER (p ≤ 0.018, d = 1.22) of the dominant shoulder initially. When groups crossed-over, the TMRG experienced a decrease in mean IR and ER after the dynamic warm-up, whereas the TWG experienced a significant increase in mean IR (p ≤ 0.001, d = 3.08) and ER (p ≤ 0.001, d = 2.56) after TMR intervention. Total Motion Release increased IR and ER of the dominant shoulder more than a dynamic warm-up. Dynamic warm-up after TMR also resulted in decreased IR and ER; however, TMR after dynamic warm-up significantly improved IR and ER. Based on these results, TMR is more effective than a generic dynamic warm-up for improving dominant shoulder ROM in baseball players.

Design of a superconducting accelerator for positron annihilation spectroscopy

International Nuclear Information System (INIS)

Oshima, Nagayasu; Kuroda, Ryunosuke; Suzuki, Ryoichi; Kinomura, Atsushi; Ohdaira, Toshiyuki; Hayashizaki, Noriyosu; Hattori, Toshiyuki

2008-01-01

A design of a superconducting accelerator for a positron beam with energy of ∼1 MeV for positron annihilation spectroscopy is proposed. The total system can be extremely small with an application of superconducting technology. Both a miniaturization and easy maintenance of the accelerator can be achieved by usage of a small liquidless refrigerator for cooling of a superconducting RF cavity. Moreover, operation duty cycle of the superconducting cavity is ∼100%. The required RF power to drive the system is only ∼10 W, therefore a large-size klystron is not necessary. The designed system including a slow positron source is small (∼2 m 3 ) enough to be used in a general laboratory. (author)

Manufacturing the MFTF magnet

International Nuclear Information System (INIS)

Dalder, E.N.C.; Hinkle, R.E.; Hodges, A.J.

1980-01-01

The Mirror Fusion Test Facility (MFTF) is a large mirror program experiment for magnetic fusion energy. It will combine and extend the near-classical plasma confinement achieved in 2XIIB with advanced neutral-beam and magnet technologies. The product of ion density and confinement time will be improved more than an order of magnitude, while the superconducting magnet weight will be extrapolated from 15 tons in Baseball II to 375 tons in MFTF. Recent reactor studies show that the MFTF will traverse much of the distance in magnet technology towards the reactor regime

Sports Adaptations for Unilateral and Bilateral Upper-Limb Amputees: Archery/Badminton/Baseball/Softball/Bowling/Golf/Table Tennis.

Science.gov (United States)

Cowart, Jim

1979-01-01

The booklet discusses sports adaptations for unilateral and bilateral upper limb amputees. Designs for adapted equipment are illustrated and information on adaptations are described for archery (including an archery release aid and a stationary bow holder); badminton (serving tray); baseball/softball (adaptations for catching, throwing, and…

Relationship of biomechanical factors to baseball pitching velocity: within pitcher variation.

Science.gov (United States)

Stodden, David F; Fleisig, Glenn S; McLean, Scott P; Andrews, James R

2005-02-01

To reach the level of elite, most baseball pitchers need to consistently produce high ball velocity but avoid high joint loads at the shoulder and elbow that may lead to injury. This study examined the relationship between fastball velocity and variations in throwing mechanics within 19 baseball pitchers who were analyzed via 3-D high-speed motion analysis. Inclusion in the study required each one to demonstrate a variation in velocity of at least 1.8 m/s (range 1.8-3.5 m/s) during 6 to 10 fastball pitch trials. Three mixed model analyses were performed to assess the independent effects of 7 kinetic, 11 temporal, and 12 kinematic parameters on pitched ball velocity. Results indicated that elbow flexion torque, shoulder proximal force, and elbow proximal force were the only three kinetic parameters significantly associated with increased ball velocity. Two temporal parameters (increased time to max shoulder horizontal adduction and decreased time to max shoulder internal rotation) and three kinematic parameters (decreased shoulder horizontal adduction at foot contact, decreased shoulder abduction during acceleration, and increased trunk tilt forward at release) were significantly related to increased ball velocity. These results point to variations in an individual's throwing mechanics that relate to pitched ball velocity, and also suggest that pitchers should focus on consistent mechanics to produce consistently high fastball velocities. In addition, pitchers should strengthen shoulder and elbow musculature that resist distraction as well as improve trunk strength and flexibility to maximize pitching velocity and help prevent injury.

Superconductivity

International Nuclear Information System (INIS)

Langone, J.

1989-01-01

This book explains the theoretical background of superconductivity. Includes discussion of electricity, material fabrication, maglev trains, the superconducting supercollider, and Japanese-US competition. The authors reports the latest discoveries

ac superconducting articles

International Nuclear Information System (INIS)

Meyerhoff, R.W.

1977-01-01

A noval ac superconducting cable is described. It consists of a composite structure having a superconducting surface along with a high thermally conductive material wherein the superconducting surface has the desired physical properties, geometrical shape and surface finish produced by the steps of depositing a superconducting layer upon a substrate having a predetermined surface finish and shape which conforms to that of the desired superconducting article, depositing a supporting layer of material on the superconducting layer and removing the substrate, the surface of the superconductor being a replica of the substrate surface

High-temperature superconductivity

International Nuclear Information System (INIS)

Ginzburg, V.L.

1987-07-01

After a short account of the history of experimental studies on superconductivity, the microscopic theory of superconductivity, the calculation of the control temperature and its possible maximum value are presented. An explanation of the mechanism of superconductivity in recently discovered superconducting metal oxide ceramics and the perspectives for the realization of new high-temperature superconducting materials are discussed. 56 refs, 2 figs, 3 tabs

Superconducting accelerator technology

International Nuclear Information System (INIS)

Grunder, H.A.; Hartline, B.K.

1986-01-01

Modern and future accelerators for high energy and nuclear physics rely increasingly on superconducting components to achieve the required magnetic fields and accelerating fields. This paper presents a practical overview of the phenomenon of superconductivity, and describes the design issues and solutions associated with superconducting magnets and superconducting rf acceleration structures. Further development and application of superconducting components promises increased accelerator performance at reduced electric power cost

Detrending career statistics in professional baseball: Accounting for the steroids era and beyond

OpenAIRE

Petersen, Alexander M.; Penner, Orion; Stanley, H. Eugene

2010-01-01

There is a long standing debate over how to objectively compare the career achievements of professional athletes from different historical eras. Developing an objective approach will be of particular importance over the next decade as Major League Baseball (MLB) players from the "steroids era" become eligible for Hall of Fame induction. Here we address this issue, as well as the general problem of comparing statistics from distinct eras, by detrending the seasonal statistics of professional b...

The large superconducting solenoids for the g-2 muon storage ring

International Nuclear Information System (INIS)

Bunce, G.; Cullen, J.; Danby, G.

1994-01-01

The g-2 muon storage ring at Brookhaven National Laboratory consists of four large superconducting solenoids. The two outer solenoids, which are 15.1 meters in diameter, share a common cryostat. The two inner solenoids, which are 13.4 meters in diameter, are in separate cryostats. The two 24 turn inner solenoids are operated at an opposite polarity from the two 24 turn outer solenoids. This generates a dipole field between the inner and outer solenoids. The flux between the solenoids is returned through a C shaped iron return yoke that also shapes the dipole field. The integrated field around the 14 meter diameter storage ring must be good to about 1 part in one million over the 90 mm dia. circular cross section where the muons are stored, averaged over the azimuth. When the four solenoids carry their 5300 A design current, the field in the 18 centimeter gap between the poles is 1.45 T. When the solenoid operates at its design current 5.5 MJ is stored between the poles. The solenoids were wound on site at Brookhaven National Laboratory. The cryostats were built around the solenoid windings which are indirectly cooled using two-phase helium

Superconducting technology

International Nuclear Information System (INIS)

2010-01-01

Superconductivity has a long history of about 100 years. Over the past 50 years, progress in superconducting materials has been mainly in metallic superconductors, such as Nb, Nb-Ti and Nb 3 Sn, resulting in the creation of various application fields based on the superconducting technologies. High-T c superconductors, the first of which was discovered in 1986, have been changing the future vision of superconducting technology through the development of new application fields such as power cables. On basis of these trends, future prospects of superconductor technology up to 2040 are discussed. In this article from the viewpoints of material development and the applications of superconducting wires and electronic devices. (author)

How Do Batters Use Visual, Auditory, and Tactile Information about the Success of a Baseball Swing?

Science.gov (United States)

Gray, Rob

2009-01-01

Bat/ball contact produces visual (the ball leaving the bat), auditory (the "crack" of the bat), and tactile (bat vibration) feedback about the success of the swing. We used a batting simulation to investigate how college baseball players use visual, tactile, and auditory feedback. In Experiment 1, swing accuracy (i.e., the lateral separation…

Decay and snapback in superconducting accelerator magnets

OpenAIRE

Haverkamp, M.

2003-01-01

This thesis deals with the explanation and compensation of the effects ‘decay’ and ‘snapback’ in superconducting accelerator magnets, in particular in those used in the new Large Hardron Collider at CERN. During periods of constant magnet excitation, as for example during the injection of particles in the storage ring, the magnetic field in superconducting accelerator magnets shows a decay behavior. As soon as the particles are accelerated, the magnets are ramped, and the magnetic field ‘snap...

Concussions are associated with decreased batting performance among Major League Baseball players.

Science.gov (United States)

Wasserman, Erin B; Abar, Beau; Shah, Manish N; Wasserman, Daniel; Bazarian, Jeffrey J

2015-05-01

Concussions impair balance, visual acuity, and reaction time--all of which are required for high-level batting performance--but the effects of concussion on batting performance have not been reported. The authors examined this relationship between concussion and batting performance among Major League Baseball (MLB) players. Batting performance among concussed MLB players will be worse upon return to play than batting performance among players missing time for noninjury reasons. Cohort study; Level of evidence, 3. The authors identified MLB players who sustained a concussion between 2007 and 2013 through league disabled-list records and a Baseball Prospectus database. For a comparison group, they identified players who went on paternity or bereavement leave during the same period. Using repeated-measures generalized linear models, the authors compared 7 batting metrics between the 2 groups for the 2 weeks upon return, as well as 4 to 6 weeks after return, controlling for pre-leave batting metrics, number of days missed, and position. The authors identified 66 concussions and 68 episodes of bereavement/paternity leave to include in the analysis. In the 2 weeks after return, batting average (.235 vs .266), on-base percentage (.294 vs .326), slugging percentage (.361 vs .423), and on-base plus slugging (.650 vs .749) were significantly lower among concussed players relative to the bereavement/paternity leave players (time×group interaction, Pperformance after concussion is adversely affected and to identify better measures to use for return-to-play decisions. © 2015 The Author(s).

Prospective multifactorial analysis of preseason risk factors for shoulder and elbow injuries in high school baseball pitchers.

Science.gov (United States)

Shitara, Hitoshi; Kobayashi, Tsutomu; Yamamoto, Atsushi; Shimoyama, Daisuke; Ichinose, Tsuyoshi; Tajika, Tsuyoshi; Osawa, Toshihisa; Iizuka, Haku; Takagishi, Kenji

2017-10-01

To prospectively identify preseason physical factors for shoulder and elbow injuries during the season in high school baseball pitchers. The study included 105 high school baseball pitchers [median age 16 (15-17) years]. The range of motion of the shoulder (90° abducted external and internal rotation) and elbow (extension/flexion), shoulder muscle strength (abduction and prone internal and external rotation), shoulder and elbow laxity, horizontal flexion, and scapular dyskinesis were assessed. After the season, the participants completed questionnaires regarding shoulder and/or elbow injuries, with injury defined as an inability to play for ≥1 week due to elbow/shoulder problems. The results of two groups (injured and noninjured) were compared using t tests and Chi-square analyses. Stepwise forward logistic regression models were developed to identify risk factors. Twenty-one injuries were observed. In univariate analysis, 90° abducted internal rotation and total arc of the dominant shoulder and the ratio of prone external rotation in the dominant to nondominant sides in the injured group were significantly less than those in the noninjured group (P = 0.02, 0.04, and 0.01, respectively). In logistic regression analysis, 90° abducted internal rotation in the dominant shoulder and prone external rotation ratio were significantly associated with injuries (P = 0.02 and 0.03, respectively). A low prone external rotation ratio and decreased 90° abducted internal rotation in the dominant shoulder in the preseason were significant risk factors for shoulder and elbow injuries in high school baseball pitchers. The results may contribute to reduce the incidence of these injuries. II.

Requirements for accuracy of superconducting coils in the Large Helical Device

Energy Technology Data Exchange (ETDEWEB)

Yamazaki, K; Yanagi, N; Ji, H; Kaneko, H; Ohyabu, N; Satow, T; Morimoto, S; Yamamoto, J; Motojima, O [National Inst. for Fusion Science, Chikusa, Nagoya (Japan); LHD Design Group

1993-01-01

Irregular magnetic fields resonate with the rational surface of the magnetic confinement systems, form magnetic islands and ergodic layers, and destruct the plasma confinement. To avoid this confinement destruction the requirement of an accuracy of 10[sup -4] in the magnetic field is adopted as the magnetic-accuracy design criterion for the LHD machine. Following this criterion the width of the undesirable magnetic island is kept less than one tenth of the plasma radius. The irregular magnetic field from the superconducting (SC) helical and poloidal coils is produced by winding irregularity, installing irregularity, cooling-down deformations and electromagnetic deformations. The local irregularities such as feeders, layer connections, adjacent-conductor connections of the coils also produce an error field. The eddy currents on the supporting shell structure of SC coils, the cryostat, etc. are also evaluated. All irregular effects are analyzed using Fourier decomposition and field mapping methods for the LHD design, and it is confirmed that the present design of the superconducting coil system satisfies the design criterion for these field irregularities. (orig.).

Pantechnik new superconducting ion source: PantechniK Indian Superconducting Ion Source

International Nuclear Information System (INIS)

Gaubert, G.; Bieth, C.; Bougy, W.; Brionne, N.; Donzel, X.; Leroy, R.; Sineau, A.; Vallerand, C.; Villari, A. C. C.; Thuillier, T.

2012-01-01

The new ECR ion source PantechniK Indian Superconducting Ion Source (PKISIS) was recently commissioned at Pantechnik. Three superconducting coils generate the axial magnetic field configuration, while the radial magnetic field is done with the multi-layer permanent magnets. Special care was devoted to the design of the hexapolar structure, allowing a maximum magnetic field of 1.32 T at the wall of the 82 mm diameter plasma chamber. The three superconducting coils using low temperature superconducting wires are cooled by a single double stage cryo-cooler (4.2 K). Cryogen-free technology is used, providing reliability and easy maintenance at low cost. The maximum installed RF power (18.0 GHz) is of 2 kW. Metallic beams can be produced with an oven (T max = 1400 deg. C) installed with an angle of 5 deg. with respect to the source axis or a sputtering system, mounted on the axis of the source. The beam extraction system is constituted of three electrodes in accel-decel configuration. The new source of Pantechnik is conceived for reaching optimum performances at 18 GHz RF frequencies. PKISIS magnetic fields are 2.1 T axial B inj and 1.32 T radial field in the wall, variable B min with an independent coil and a large and opened extraction region. Moreover, PKISIS integrates modern design concepts, like RF direct injection (2 kW availability), dc-bias moving disk, out-of-axis oven and axial sputtering facility for metal beams. Finally, PKISIS is also conceived in order to operate in a high-voltage platform with minor power consumption.

Private Financing and Sports Franchise Values: The Case of Major League Baseball

OpenAIRE

Phillip Miller

2006-01-01

This paper examines the impact of receiving a new stadium on team franchise values. I argue that a new stadium will increase the franchise values of teams regardless of how construction was financed. A team playing in a stadium that it owns will be able to capitalize the value of the stadium in the team’s franchise value and will thus have a higher franchise value. Using panel data for Major League Baseball teams from 1990-2002, I find that, after controlling for team quality and metro area d...

Superconductivity

CERN Document Server

Ketterson, John B

2008-01-01

Conceived as the definitive reference in a classic and important field of modern physics, this extensive and comprehensive handbook systematically reviews the basic physics, theory and recent advances in the field of superconductivity. Leading researchers, including Nobel laureates, describe the state-of-the-art in conventional and unconventional superconductors at a particularly opportune time, as new experimental techniques and field-theoretical methods have emerged. In addition to full-coverage of novel materials and underlying mechanisms, the handbook reflects continued intense research into electron-phone based superconductivity. Considerable attention is devoted to high-Tc superconductivity, novel superconductivity, including triplet pairing in the ruthenates, novel superconductors, such as heavy-Fermion metals and organic materials, and also granular superconductors. What’s more, several contributions address superconductors with impurities and nanostructured superconductors. Important new results on...

Computation of Superconducting Generators for Wind Turbine Applications

DEFF Research Database (Denmark)

Rodriguez Zermeno, Victor Manuel

The idea of introducing a superconducting generator for offshore wind turbine applications has received increasing support. It has been proposed as a way to meet energy market requirements and policies demanding clean energy sources in the near future. However, design considerations have to take......, to the actual generators in the KW (MW) class with an expected cross section in the order of decimeters (meters). This thesis work presents cumulative results intended to create a bottom-up model of a synchronous generator with superconducting rotor windings. In a first approach, multiscale meshes with large...... of the generator including ramp-up of rotor coils, load connection and change was simulated. Hence, transient hysteresis losses in the superconducting coils were computed. This allowed addressing several important design and performance issues such as critical current of the superconducting coils, electric load...

Theoretical studies of superconductivity in doped BaCoSO

Science.gov (United States)

Qin, Shengshan; Li, Yinxiang; Zhang, Qiang; Le, Congcong; Hu, Jiangping

2018-06-01

We investigate superconductivity that may exist in the doped BaCoSO, a multi-orbital Mott insulator with a strong antiferromagnetic ground state. The superconductivity is studied in both t-J type and Hubbard type multi-orbital models by mean field approach and random phase approximation (RPA) analysis. Even if there is no C 4 rotational symmetry, it is found that the system still carries a d-wave like pairing symmetry state with gapless nodes and sign changed superconducting order parameters on Fermi surfaces. The results are largely doping insensitive. In this superconducting state, the three {t_{{2_g}}} orbitals have very different superconducting form factors in momentum space. In particular, the intra-orbital pairing of the {d_{{x^2} - {y^2}}} orbital has an s-wave like pairing form factor. The two methods also predict very different pairing strength on different parts of Fermi surfaces. These results suggest that BaCoSO and related materials can be a new ground to test and establish fundamental principles for unconventional high temperature superconductivity.

Laser startup optics for Baseball II and future mirror machines

International Nuclear Information System (INIS)

Frank, A.M.; Chargin, A.K.; Brown, N.J.

1975-01-01

The laser startup system for Baseball II-T uses a 300-J CO 2 laser to hit a 100-μ diameter pellet with a laser power density on the order of 10 13 W/cm 2 . The laser is a 20-cm diameter unstable resonator transversely excited (TEA) oscillator. The beam is split and then focused using off-axis parabolas. The symmetric configuration and central obscuration of the CO 2 beam allow coaxial alignment and pellet detection optics. This experiment primarily uses commercially available systems and components. Optical elements were fabricated both by direct machining and standard polishing techniques. The laser and optical systems are directly scalable to reactor requirements using demonstrated technologies

Superconductivity revisited

CERN Document Server

Dougherty, Ralph

2013-01-01

While the macroscopic phenomenon of superconductivity is well known and in practical use worldwide in many industries, including MRIs in medical diagnostics, the current theoretical paradigm for superconductivity (BCS theory) suffers from a number of limitations, not the least of which is an adequate explanation of high temperature superconductivity. This book reviews the current theory and its limitations and suggests new ideas and approaches in addressing these issues. The central objective of the book is to develop a new, coherent, understandable theory of superconductivity directly based on molecular quantum mechanics.

High field superconducting magnets

Science.gov (United States)

Hait, Thomas P. (Inventor); Shirron, Peter J. (Inventor)

2011-01-01

A superconducting magnet includes an insulating layer disposed about the surface of a mandrel; a superconducting wire wound in adjacent turns about the mandrel to form the superconducting magnet, wherein the superconducting wire is in thermal communication with the mandrel, and the superconducting magnet has a field-to-current ratio equal to or greater than 1.1 Tesla per Ampere; a thermally conductive potting material configured to fill interstices between the adjacent turns, wherein the thermally conductive potting material and the superconducting wire provide a path for dissipation of heat; and a voltage limiting device disposed across each end of the superconducting wire, wherein the voltage limiting device is configured to prevent a voltage excursion across the superconducting wire during quench of the superconducting magnet.

Multi-gap superconductivity in MgB2: Magneto-Raman spectroscopy

International Nuclear Information System (INIS)

Blumberg, G.; Mialitsin, A.; Dennis, B.S.; Zhigadlo, N.D.; Karpinski, J.

2007-01-01

Electronic Raman scattering studies on MgB 2 single crystals as a function of excitation and polarization have revealed three distinct superconducting features: a clean gap below 37 cm -1 and two coherence peaks at 109 and 78 cm -1 which we identify as the superconducting gaps in π- and σ-bands and as the Leggett's collective mode arising from the fluctuation in the relative phase between two superconducting condensates residing on corresponding bands. The temperature and field dependencies of the superconducting features have been established. A phononic Raman scattering study of the E 2g boron stretching mode anharmonicity and of superconductivity induced self-energy effects is presented. We show that anharmonic two phonon decay is mainly responsible for the unusually large linewidth of the E 2g mode. We observe ∼2.5% hardening of the E 2g phonon frequency upon cooling into the superconducting state and estimate the electron-phonon coupling strength associated with this renormalization

Design, construction, and performance of superconducting magnet support posts for the Large Hadron Collider

International Nuclear Information System (INIS)

Blin, M.; Danielsson, H.; Evans, B.; Mathieu, M.

1994-01-01

Different support posts for the Large Hadron Collider (LHC) prototype superconducting magnets have been designed and manufactured. They have been evaluated both mechanically and thermally. The posts are made of a tubular section in composite materials, i.e. glass- or carbon-fibre and epoxy resin, with glued metallic heat intercepts and connections. Mechanical tests have been carried out with both radial and axial loads, before and after cooldown to working temperature. The design considerations and future developments concerning dimensions and other materials are also discussed in this paper. Thermal performance has been evaluated at 1.8 K, 5 K and 80 K in a precision heat leak measuring bench. The measurements have been carried out using calibrated thermal conductances (open-quotes heatmetersclose quotes) and boil-off methods. The measured performances of the posts have been compared with analytical predictions

A superconducting magnetic gear

International Nuclear Information System (INIS)

Campbell, A M

2016-01-01

A comparison is made between a magnetic gear using permanent magnets and superconductors. The objective is to see if there are any fundamental reasons why superconducting magnets should not provide higher power densities than permanent magnets. The gear is based on the variable permeability design of Attilah and Howe (2001 IEEE Trans. Magn. 37 2844–46) in which a ring of permanent magnets surrounding a ring of permeable pole pieces with a different spacing gives an internal field component at the beat frequency. Superconductors can provide much larger fields and forces but will saturate the pole pieces. However the gear mechanism still operates, but in a different way. The magnetisation of the pole pieces is now constant but rotates with angle at the beat frequency. The result is a cylindrical Halbach array which produces an internal field with the same symmetry as in the linear regime, but has an analytic solution. In this paper a typical gear system is analysed with finite elements using FlexPDE. It is shown that the gear can work well into the saturation regime and that the Halbach array gives a good approximation to the results. Replacing the permanent magnets with superconducting tapes can give large increases in torque density, and for something like a wind turbine a combined gear and generator is possible. However there are major practical problems. Perhaps the most fundamental is the large high frequency field which is inevitably present and which will cause AC losses. Also large magnetic fields are required, with all the practical problems of high field superconducting magnets in rotating machines. Nevertheless there are ways of mitigating these difficulties and it seems worthwhile to explore the possibilities of this technology further. (paper)

Superconducting nano-strip particle detectors

International Nuclear Information System (INIS)

Cristiano, R; Ejrnaes, M; Casaburi, A; Zen, N; Ohkubo, M

2015-01-01

We review progress in the development and applications of superconducting nano-strip particle detectors. Particle detectors based on superconducting nano-strips stem from the parent devices developed for single photon detection (SSPD) and share with them ultra-fast response times (sub-nanosecond) and the ability to operate at a relatively high temperature (2–5 K) compared with other cryogenic detectors. SSPDs have been used in the detection of electrons, neutral and charged ions, and biological macromolecules; nevertheless, the development of superconducting nano-strip particle detectors has mainly been driven by their use in time-of-flight mass spectrometers (TOF-MSs) where the goal of 100% efficiency at large mass values can be achieved. Special emphasis will be given to this case, reporting on the great progress which has been achieved and which permits us to overcome the limitations of existing mass spectrometers represented by low detection efficiency at large masses and charge/mass ambiguity. Furthermore, such progress could represent a breakthrough in the field. In this review article we will introduce the device concept and detection principle, stressing the peculiarities of the nano-strip particle detector as well as its similarities with photon detectors. The development of parallel strip configuration is introduced and extensively discussed, since it has contributed to the significant progress of TOF-MS applications. (paper)

Quantum Devices Bonded Beneath a Superconducting Shield: Part 2

Science.gov (United States)

McRae, Corey Rae; Abdallah, Adel; Bejanin, Jeremy; Earnest, Carolyn; McConkey, Thomas; Pagel, Zachary; Mariantoni, Matteo

The next-generation quantum computer will rely on physical quantum bits (qubits) organized into arrays to form error-robust logical qubits. In the superconducting quantum circuit implementation, this architecture will require the use of larger and larger chip sizes. In order for on-chip superconducting quantum computers to be scalable, various issues found in large chips must be addressed, including the suppression of box modes (due to the sample holder) and the suppression of slot modes (due to fractured ground planes). By bonding a metallized shield layer over a superconducting circuit using thin-film indium as a bonding agent, we have demonstrated proof of concept of an extensible circuit architecture that holds the key to the suppression of spurious modes. Microwave characterization of shielded transmission lines and measurement of superconducting resonators were compared to identical unshielded devices. The elimination of box modes was investigated, as well as bond characteristics including bond homogeneity and the presence of a superconducting connection.

Safety concerns for superconducting magnets of upcoming fusion experiments

International Nuclear Information System (INIS)

Turner, L.R.

1983-01-01

-Several fusion experiments being constructed (Tore Supra) or contemplated (DCT 8, Alcator DCT) feature superconducting coils. These coils introduce the following safety concerns: 1. Internally Cooled Conductor (ICC). ICC's are found to be highly stable against short heat pulses, even when the coolant is stagnant or moving at low steady-state velocity. However, a large heat pulse is certain to quench the conductor. Thus, determining the stability limits is vital. 2. Helium II Cooling. Helium II has both unique advantages as a coolant and unique safety problems. 3. Shorted Turns. In magnets with shorts from operational accidents, the current can switch back and forth between the short and the shorted turns, as those alternatively go normal and superconducting. 4. Hybrid Superconducting-Normal Conducting Coil System. The possibility of unequal currents in the different magnets and thus of unexpected forces on the superconducting magnets is much greater than for an all-superconducting system. Analysis of these problems are presented

Superconducting energy store

International Nuclear Information System (INIS)

Elsel, W.

1986-01-01

The advantages obtained by the energy store device according to the invention with a superconducting solenoid system consist of the fact that only relatively short superconducting forward and return leads are required, which are collected into cables as far as possible. This limits the coolant losses of the cables. Only one relatively expensive connecting part with a transition of its conductors from room temperature to a low temperature is required, which, like the normal conducting current switch, is easily accessible. As the continuation has to be cooled independently of the upper part solenoid, cooling of this continuation part can prevent the introduction of large quantities of heat into the connected part solenoid. Due to the cooling of the forward and return conductors of the connecting cable with the coolant of the lower part solenoid, there are relatively few separations between the coolant spaces of the part solenoids. (orig./MM) [de

Superconductivity in Medicine

Science.gov (United States)

Alonso, Jose R.; Antaya, Timothy A.

2012-01-01

Superconductivity is playing an increasingly important role in advanced medical technologies. Compact superconducting cyclotrons are emerging as powerful tools for external beam therapy with protons and carbon ions, and offer advantages of cost and size reduction in isotope production as well. Superconducting magnets in isocentric gantries reduce their size and weight to practical proportions. In diagnostic imaging, superconducting magnets have been crucial for the successful clinical implementation of magnetic resonance imaging. This article introduces each of those areas and describes the role which superconductivity is playing in them.

Exciton interaction: its possible role in high temperature superconductivity

International Nuclear Information System (INIS)

Little, W.A.

1987-01-01

The recent remarkable developments in superconductivity has forced the group of physicists in the main stream of superconductivity research to re-examine the possible role of what has been referred to in the conference as novel mechanisms of superconductivity. The exciton mechanism is one such. While the many studies and developments in this subject are relatively well known to those involved in studies of organic superconductors and superconductors of reduced dimension, it appears that it is not well known to that large body of physicists involved in the more conventional mainstream of superconductivity. The salient features of the mechanism are reviewed and what it can and cannot do is discussed. Remarks are based on the most recent and most comprehensive review of the subject published in 1979, plus a few key papers since that time

Estimation of the adiabatic energy limit versus beta in Baseball II

International Nuclear Information System (INIS)

Foote, J.H.

1976-01-01

Several estimates of the adiabatic energy limit versus beta in Baseball II are summarized, and the calculational methods used to obtain them are described. Some estimates are based on analytic expressions; for others, particle orbits are calculated, magnetic-moment jumps are inspected, and adiabatic limits then derived. The results are sensitive to the assumed variation of the combined vacuum-plus-plasma magnetic field. The calculated adiabatic energy limit falls rapidly with beta, even for a gradual magnetic-field variation. If we assume a sharp depression in the axial profile of the combined magnetic field for a finite-beta plasma, the adiabatic limit can be further markedly reduced

The LHC Superconducting RF System

CERN Document Server

Boussard, Daniel

1999-01-01

The European Laboratory for Particle Physics (CERN), the largest high energy physics laboratory worldwide, is constructing the Large Hadron Collider (LHC) in the existing 27 km circumference LEP (Large Electron Positron) collider tunnel. For the LHC, superconducting cavities, operating at 4.5 K, will provide the required acceleration field for ramping the beam energy up to 7 TeV and for keeping the colliding proton beams tightly bunched. Superconducting cavities were chosen, not only because of their high acceleration field leading to a small contribution to the machine impedance, but also because of their high stored energy which minimises the effects of periodic transient beam loading associated with the high beam intensity (0.5 A). There will be eight single-cell cavities per beam, each delivering 2 MV (5.3 MV/m) at 400 MHz. The cavities themselves are now being manufactured by industrial firms, using niobium on copper technology which gives full satisfaction at LEP. A complete cavity prototype assembly in...

Superconducting Panofsky quadrupoles

International Nuclear Information System (INIS)

Harwood, L.H.

1981-01-01

A design for a rectangular aperture quadrupole magnet without pole-tips was introduced by Hand and Panofsky in 1959. This design was quite radical but simple to construct. Few magnets of this design were ever built because of the large power needed. With the advent of superconducting coils there has been a renewed interest in them. The mathematical basis, field characteristics, and present and future construction of these magnets are described

Predicting Intentions to Eat a Healthful Diet by College Baseball Players: Applying the Theory of Planned Behavior

Science.gov (United States)

Pawlak, Roman; Malinauskas, Brenda; Rivera, David

2009-01-01

Objective: To assess factors important to college baseball players regarding intention to eat a healthful diet within the Theory of Planned Behavior. Design: A survey based on the Theory of Planned Behavior was administered during the 2006 summer league season from 5 of the Northern Division teams of the Coastal Plain League. Participants: Male…

Stress analysis of superconducting magnets for magnetic fusion reactors

Energy Technology Data Exchange (ETDEWEB)

Akin, J.E.; Gray, W.H.; Baudry, T.V.

1980-01-01

Superconducting devices involve several factors that normally are not encountered in the structural analysis of more common systems. Several of these factors ae noted and methods for including them in an analysis are cited. To illustrate the state of the analysis art for superconducting magnets, in magnetic fusion reactors, two specific projects are illustrated. They are the Large Coil Program (LCP) and the Engineering Test Facility (ETF).

Stress analysis of superconducting magnets for magnetic fusion reactors

International Nuclear Information System (INIS)

Akin, J.E.; Gray, W.H.; Baudry, T.V.

1980-01-01

Superconducting devices involve several factors that normally are not encountered in the structural analysis of more common systems. Several of these factors ae noted and methods for including them in an analysis are cited. To illustrate the state of the analysis art for superconducting magnets, in magnetic fusion reactors, two specific projects are illustrated. They are the Large Coil Program (LCP) and the Engineering Test Facility

Superconducting classes in heavy fermions systems

International Nuclear Information System (INIS)

Volovik, G.E.; Gor'kov, L.P.

1985-01-01

A mathematical method for constructing of the superconductivity classes for nontrivial superconductors is described. All superconducting phases which can arise directly on transition from the normal state for cubic, hexagonal and tetragonal symmetries are enumerated. It is shown that in the triplet case the types of zeros in the energy gap always correspond to points on the Fermi surface, whereas for signlet pairing the whole zero lines are possible. For the phases with zeros on the lines or points, the low-temperature specific heat varies as T 2 on T 3 respectivelty. The superconducting phases which arise from the multydimensional representations may possess a magnetic moment which induces currents on the surface of a monodomain sample even in the absence of an external magnetic field. The specific case of a domain wall is considered and it is shown that large magnetic currents of magnetization are present in the wall

Editorial Commentary: Changing Times in Sports Biomechanics: Baseball Pitching Injuries and Emerging Wearable Technology.

Science.gov (United States)

Fleisig, Glenn S

2018-03-01

Research has shown relations between amount of baseball pitching and overuse injuries, as well as between poor mechanics and high loads on the elbow and shoulder. However, overuse injuries continue to be a problem from youth to professional sports. Emerging wearable technology may enable players, parents, coaches, leagues, and clinicians to monitor biomechanics during competition and training, reducing the risk of serious injury. Copyright © 2017 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Modern technologies in rf superconductivity

International Nuclear Information System (INIS)

Lengeler, H.

1994-01-01

The development and application of superconducting rf cavities in particle accelerators is a fine example of advanced technology and of close cooperation with industry. This contribution examines the theoretical and present-day practical limitations of sc cavities and describes some advanced technologies needed for their large scale applications. (orig.)

Designing of superconducting magnet for clinical MRI

International Nuclear Information System (INIS)

Kar, Soumen; Choudhury, A.; Sharma, R.G.; Datta, T.S.

2015-01-01

Superconducting technology of Magnetic Resonance Imaging (MRI) scanner is closely guarded technology as it has huge commercial application for clinical diagnostics. This is a rapidly evolving technology which requires innovative design of magnetic and cryogenic system. A project on the indigenous development of 1.5 T (B_0) MRI scanner has been initiated by SAMEER, Mumbai funded by DeitY, Gov. of India. IUAC is the collaborating institute for designing and developing the superconducting magnets and the cryostat for 1.5 T MRI scanner. The superconducting magnet is heart of the present day MRI system. The performance of the magnet has the highest impact on the overall image quality of the scanner. The stringent requirement of the spatial homogeneity (few parts per million within 50 cm diametrical spherical volume), the temporal stability (0.1 ppm/hr.) of the superconducting magnet and the safety standard (5 G in 5 m x 3 m ellipsoidal space) makes the designing of the superconducting magnet more complex. MRI consists of set of main coils and shielding coils. The large ratio between the diameter and the winding length of each coil makes the B_p_e_a_k/B_0 ratio much higher, which makes complexity in selecting the load line of the magnet. Superconducting magnets will be made of NbTi wire-in-channel (WIC) conductor with high copper to superconducting (NbTi) ratio. Multi-coil configuration on multi-bobbin architecture is though is cost effective but poses complexity in the mechanical integration to achieve desired homogeneity. Some of the major sources of inhomogeneities, in a multi-bobbin configuration, are the imperfect axial positioning and angular shift. We have simulated several factors which causes the homogeneity in six (main) coils configuration for a 1.5 T MRI magnet. Differential thermal shrinkage between the bobbin and superconducting winding is also a major source of inhomogeneity in a MRI magnet. This paper briefly present the different designing aspects of the

Detection of Resistive Transitions in LHC Superconducting Components

OpenAIRE

Denz, R; Rodríguez-Mateos, F

2001-01-01

The LHC has entered the construction phase. It will incorporate a large number of superconducting components like magnets, current leads and busbars. All these components require protection means in case of a transition from the superconducting to the resistive state, the so-called quench. Key elements in the protection system are electronic quench detectors, which have to be able to identify a quench in any state of the powering cycle of the accelerator. According to the different properties...

Improvements in or relating to the manufacture of superconducting members

International Nuclear Information System (INIS)

Lee, J.A.; Madsen, P.E.; Hills, R.F.

1980-01-01

A method is described for the manufacture of superconducting members; more particularly of a superconducting member comprising a large number of fine superconductive filaments supported in an electrically conductive, non-superconductive matrix. The method embodies a superconductor of A 15 crystal structure having the general formula A 3 B (where A is a substrate metal (preferably niobium or vanadium) and B is one or more elements (e.g. tin, germanium) which when alloyed with A will form the superconductor). The method involves, as one step, forming an alloy of a carrier metal (e.g. copper) with the element B, and an essential condition of the method is that the phosphorus content of the alloy is less than 0.2 per cent by weight. (U.K.)

Development work on superconducting coils for a Large Mirror Fusion Test Facility

International Nuclear Information System (INIS)

Cornish, D.N.; Deis, D.W.; Harvey, A.R.; Hirzel, D.G.; Johnston, J.E.; Leber, R.L.; Nelson, R.L.; Zbasnik, J.P.

1977-01-01

This article has summarized development work directed toward obtaining the data required to design and build the superconducting coils for MFTF. The methods for fabricating the conductor and joining lengths of the conductor are almost finalized, and the building of the test coil and associated equipment is now well under way

JETC (Japanese Technology Evaluation Center) Panel Report on High Temperature Superconductivity in Japan

Science.gov (United States)

Shelton, Duane; Gamota, George

1989-01-01

The Japanese regard success in R and D in high temperature superconductivity as an important national objective. The results of a detailed evaluation of the current state of Japanese high temperature superconductivity development are provided. The analysis was performed by a panel of technical experts drawn from U.S. industry and academia, and is based on reviews of the relevant literature and visits to Japanese government, academic and industrial laboratories. Detailed appraisals are presented on the following: Basic research; superconducting materials; large scale applications; processing of superconducting materials; superconducting electronics and thin films. In all cases, comparisons are made with the corresponding state-of-the-art in the United States.

Novel Approach to Linear Accelerator Superconducting Magnet System

International Nuclear Information System (INIS)

Kashikhin, Vladimir

2011-01-01

Superconducting Linear Accelerators include a superconducting magnet system for particle beam transportation that provides the beam focusing and steering. This system consists of a large number of quadrupole magnets and dipole correctors mounted inside or between cryomodules with SCRF cavities. Each magnet has current leads and powered from its own power supply. The paper proposes a novel approach to magnet powering based on using superconducting persistent current switches. A group of magnets is powered from the same power supply through the common, for the group of cryomodules, electrical bus and pair of current leads. Superconducting switches direct the current to the chosen magnet and close the circuit providing the magnet operation in a persistent current mode. Two persistent current switches were fabricated and tested. In the paper also presented the results of magnetic field simulations, decay time constants analysis, and a way of improving quadrupole magnetic center stability. Such approach substantially reduces the magnet system cost and increases the reliability.

Target-plasma production by laser irradiation of a pellet in the Baseball II-T experiment

International Nuclear Information System (INIS)

Damm, C.C.; Foote, J.H.; Futch, A.H.; Goodman, R.K.; Hornady, R.S.; Osher, J.E.; Porter, G.D.

1977-01-01

One way to generate a plasma target that can be used in conjunction with an injected neutral beam to initiate a high-energy plasma in a steady-state, magnetic-mirror field is by the laser irradiation of a solid pellet located within the confinement region. In the Lawrence Livermore Laboratory Baseball II-T experiment, a CO 2 laser was used to provide a two-sided irradiation of an ammonia pellet; the maximum laser intensity on the pellet was approximately 4 x 10 12 W/cm 2 . The 150-μm-dia pellets were guided to the laser focal spot in the Baseball II-T magnetic field using steering voltages controlled by a microcomputer-based system. Diagnostics showed complete ionization of the pellet, average ion energies in the keV range, synchronized triggering of the laser and the neutral beam, and rapid expansion of the plasma to a diameter that was a good match to the diameter of the neutral beam. Predictions obtained from the LASNEX code compared well with measured results. Although the laser-pellet approach was proven usable as a target-plasma startup system, it would be much more complicated and expensive than the method in which streaming plasma is used to trap the neutal beams

Development of superconducting pulsed poloidal coil in JAERI

International Nuclear Information System (INIS)

Shimamoto, S.; Okuno, K.; Ando, T.; Tsuji, H.

1990-01-01

In the Japan Atomic Energy Research Institute, (JAERI), development work on pulsed superconductors and coils started in 1979, aiming at the demonstration of the applicability of superconducting technologies to pulsed poloidal coils in a fusion reactor. Initially our effort was concentrated mainly on the development of pool-cooled large-current pulsed conductors. Over the past ten years, superconducting technology has made great progress and the forced-flow cooled coil has assumed great importance in the development work. Now the Demo Poloidal Coil Project is in progress in JAERI, and three large forced-flow cooled coils have so far been fabricated and tested. Many improvements have been achieved in ac-loss performance and mechanical characteristics. (author)

Overview of superconducting RF technology and its application to high-current linacs

International Nuclear Information System (INIS)

Delayen, J.R.; Bohn, C.L.

1994-01-01

Superconducting linacs may be a viable option for high-current applications such as copious neutron production like that needed for transmutation of radioactive waste. These linacs must run reliably for many years and allow easy routine maintenance. superconducting cavities operate efficiently with high cw gradients, properties which help to reduce operating and capital costs. However, cost effectiveness is not the sole consideration in these applications. For example, beam impingement must be essentially eliminated to prevent unsafe radioactivation of the accelerating structures, and thus large apertures are needed through which to pass the beam. Because of their high efficiency, superconducting cavities can be designed with very large bore apertures, thereby reducing the effect of beam impingement

Field quality in low-β superconducting quadrupoles and impact on the beam dynamics for the Large Hadron Collider upgrade

Directory of Open Access Journals (Sweden)

Boris Bellesia

2007-06-01

Full Text Available A possible scenario for the luminosity upgrade of the Large Hadron Collider is based on large aperture quadrupoles to lower β^{*} in the interaction regions. Here we analyze the measurements relative to the field quality of the RHIC and LHC superconducting quadrupoles to find out the dependence of field errors on the size of the magnet aperture. Data are interpreted in the framework of a Monte Carlo analysis giving the reproducibility in the coil positioning reached in each production. We show that this precision is likely to be independent of the magnet aperture. Using this result, we can carry out an estimate of the impact of the field quality on the beam dynamics for the collision optics.

Hall probe for measuring high currents in superconducting coils

International Nuclear Information System (INIS)

Ferendeci, A.M.

1986-01-01

Constructional details of a compact Hall probe for measuring high currents in superconducting coils are given. The Hall probe is easy to assemble and can be inserted or removed from the system without breaking the superconducting loop. Upper current limit of the probe can be increased by using larger magnetic core material. Shielding becomes necessary if the probe holder is to be placed near large current dependent magnetic fields

Methodology and search for superconductivity in the La-Si-C system

International Nuclear Information System (INIS)

De la Venta, J; Basaran, Ali C; Schuller, Ivan K; Grant, T; Machado, A J S; Fisk, Z; Suchomel, M R; Weber, R T

2011-01-01

In this paper we describe a methodology for the search for new superconducting materials. This consists of a parallel synthesis of a highly inhomogeneous alloy which covers large areas of the metallurgical phase diagram combined with a fast, microwave-based method which allows non-superconducting portions of the sample to be discarded. Once an inhomogeneous sample containing a minority phase superconductor is identified, we revert to well-known thorough identification methods which include standard physical and structural methods. We show how a systematic structural study helps in avoiding misidentification of new superconducting materials when there are indications from other methods of new discoveries. These ideas are applied to the La-Si-C system which exhibits promising normal state properties which are sometimes correlated with superconductivity. Although this system shows indications for the presence of a new superconducting compound, the careful analysis described here shows that the superconductivity in this system can be attributed to intermediate binary and single phases of the system.

Vacuum Technology for Superconducting Devices

Energy Technology Data Exchange (ETDEWEB)

Chiggiato, P [European Organization for Nuclear Research, Geneva (Switzerland)

2014-07-01

The basic notions of vacuum technology for superconducting applications are presented, with an emphasis on mass and heat transport in free molecular regimes. The working principles and practical details of turbomolecular pumps and cryopumps are introduced. The specific case of the Large Hadron Collider’s cryogenic vacuum system is briefly reviewed.

Preparation of MgB2 superconducting microbridges by focused ion beam direct milling

Science.gov (United States)

Zhang, Xuena; Li, Yanli; Xu, Zhuang; Kong, Xiangdong; Han, Li

2017-01-01

MgB2 superconducting microbridges were prepared by focused ion beam (FIB) direct milling on MgB2 films. The surface topography of the microbridges were observed using SEM and AFM and the superconductivity was measured in this paper. Lots of cracks and holes were found near the milled area. And the superconducting transition temperature was decreased a lot and the bridges prepared were not superconducting due to ion damage after milled with large dose. Through these works, we explored the effect regular of FIB milling and experimental parameters on the performance of microbridges.

Superconductivity and superfluidity as universal emergent phenomena in diverse physical systems

International Nuclear Information System (INIS)

Guidry, Mike

2014-01-01

Superconductivity and superfluidity are observed across a strikingly broad range of physical systems. This universality seems unlikely to be coincidental but a unified understanding of superconductivity and superfluidity across these highly disparate fields seems impossible in traditional microscopic terms. I give an overview of superconductivity and superfluidity found in various fermionic condensed matter, nuclear physics, and neutron star systems, and propose that all result from generic algebraic structures for the emergent effective Hamiltonian, with the role of underlying microscopic physics largely relegated to influence on parameter values

Research briefing on high-temperature superconductivity

Science.gov (United States)

1987-10-01

The research briefing was prepared in response to the exciting developments in superconductivity in ceramic oxide materials announced earlier in 1987. The panel's specific charge was to examine not only the scientific opportunities in high-temperature superconductivity but also the barriers to commercial exploitation. While the base of experimental knowledge on the superconductors is growing rapidly, there is as yet no generally accepted theoretical explanation of their behavior. The fabrication and processing challenges presented by the materials suggest that the period or precommercial exploration for applications will probably extend for a decade or more. Near term prospects for applications include magnetic shielding, the voltage standard, superconducting quantum interference devices, infrared sensors, microwave devices, and analog signal processing. The panel also identified a number of longer-term prospects in high-field and large-scale applications, and in electronics. The United States' competitive position in the field is discussed, major scientific and technological objectives for research and development identified, and concludes with a series of recommendations.

Contribution of Visual Information about Ball Trajectory to Baseball Hitting Accuracy.

Directory of Open Access Journals (Sweden)

Takatoshi Higuchi

Full Text Available The contribution of visual information about a pitched ball to the accuracy of baseball-bat contact may vary depending on the part of trajectory seen. The purpose of the present study was to examine the relationship between hitting accuracy and the segment of the trajectory of the flying ball that can be seen by the batter. Ten college baseball field players participated in the study. The systematic error and standardized variability of ball-bat contact on the bat coordinate system and pitcher-to-catcher direction when hitting a ball launched from a pitching machine were measured with or without visual occlusion and analyzed using analysis of variance. The visual occlusion timing included occlusion from 150 milliseconds (ms after the ball release (R+150, occlusion from 150 ms before the expected arrival of the launched ball at the home plate (A-150, and a condition with no occlusion (NO. Twelve trials in each condition were performed using two ball speeds (31.9 m·s-1 and 40.3 m·s-1. Visual occlusion did not affect the mean location of ball-bat contact in the bat's long axis, short axis, and pitcher-to-catcher directions. Although the magnitude of standardized variability was significantly smaller in the bat's short axis direction than in the bat's long axis and pitcher-to-catcher directions (p < 0.001, additional visible time from the R+150 condition to the A-150 and NO conditions resulted in a further decrease in standardized variability only in the bat's short axis direction (p < 0.05. The results suggested that there is directional specificity in the magnitude of standardized variability with different visible time. The present study also confirmed the limitation to visual information is the later part of the ball trajectory for improving hitting accuracy, which is likely due to visuo-motor delay.

Understanding and application of superconducting materials

International Nuclear Information System (INIS)

Moon, Byeong Mu; Lee, Chun Heung

1997-02-01

This book deals with superconducting materials, which contains from basic theory to application of superconducting materials. The contents of this book are mystery of superconducting materials, properties of superconducting materials, thermodynamics of superconducting materials, theoretical background of superconducting materials, tunnelling and quantum interference, classification and properties of superconducting materials, high temperature superconducting materials, production and analysis of superconducting materials and application of superconducting materials.

Structural safety features for superconducting magnets

International Nuclear Information System (INIS)

Lehner, J.; Reich, M.; Powell, J.; Bezler, P.; Gardner, D.; Yu, W.; Chang, T.Y.

1975-01-01

A survey has been carried out for various potential structural safety problems of superconducting fusion magnets. These areas include: (1) Stresses due to inhomogeneous temperature distributions in magnets where normal regions have been initiated. (2) Stress distributions and yield forces due to cracks and failed regions. (3) Superconducting magnet response due to seismic excitation. These analyses have been carried out using a variety of large capacity finite element computer codes that allow for the evaluation of stresses in elastic or elastic-plastic zones and around singularities in the magnet structure. Thus far, these analyses have been carried out on UWMAK-I type magnet systems

Overview of Superconductivity and Challenges in Applications

CERN Document Server

Flükiger, Rene

2012-01-01

Considerable progress has been achieved during the last few decades in the various fields of applied superconductivity, while the related low temperature technology has reached a high level. Magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR) are so far the most successful applications, with tens of thousands of units worldwide, but high potential can also be recognized in the energy sector, with high energy cables, transformers, motors, generators for wind turbines, fault current limiters and devices for magnetic energy storage. A large number of magnet and cable prototypes have been constructed, showing in all cases high reliability. Large projects involving the construction of magnets, solenoids as well as dipoles and quadrupoles are described in the present book. A very large project, the LHC, is currently in operation, demonstrating that superconductivity is a reliable technology, even in a device of unprecedented high complexity. A project of similar complexity is ITER, a fusion device...

Submicron superconducting structures

International Nuclear Information System (INIS)

Golovashkin, A.I.; Lykov, A.N.

1986-01-01

An overview of works concerning superconducting structures of submicron dimensions and a system of such structures is given. It is noted that usage of the above structures in superconducting microelectronics permits, first, to increase the element packing density, to decrease the signal transmission time, capacity, power dissipated in high-frequency applications. Secondly, negligible coherence length in transition metals, their alloys and high-temperature compounds also restrict the dimensions of superconducting weak couplings when the 'classical' Josephson effect is displayed. The most effective methods for production of submicron superconducting structures are the following: lithography, double scribering. Recently the systems of superconducting submicron elements are extensively studied. It is shown that such systems can be phased by magnetic field

Asymmetries in Experiential and Vicarious Feedback: Lessons from the Hiring and Firing of Baseball Managers

Directory of Open Access Journals (Sweden)

David Strang

2014-05-01

Full Text Available We examine experiential and vicarious feedback in the hiring and firing of baseball managers. Realized outcomes play a large role in both decisions; the probability that a manager will be fired is a function of the team’s win–loss record, and a manager is quicker to be rehired if his teams had won more in the past. There are substantial asymmetries, however, in the fine structure of the two feedback functions. The rate at which managers are fired is powerfully shaped by recent outcomes, falls with success and rises with failure, and adjusts for history-based expectations. By contrast, hiring reflects a longer-term perspective that emphasizes outcomes over the manager’s career as well as the most recent campaign, rewards success but does not penalize failure, and exhibits no adjustment for historical expectations. We explain these asymmetries in terms of the disparate displays of rationality that organizations enact in response to their own outcomes versus those of others. Experiential feedback is conditioned by a logic of accountability, vicarious feedback by a logic of emulation.

Contribution to the study of superconducting magnets using high transition temperature superconducting materials

International Nuclear Information System (INIS)

Lecrevisse, Thibault

2012-01-01

The new industrial superconductors using high critical temperature compounds offer new possibilities for superconducting magnetism. Indeed they allow higher magnetic field with the same classical cryogenics at 4.2 K on one hand, and on the other hand they also pave the way for superconducting magnets working between 10 K and 30 K. The high temperature superconductors are then needed in order to produce magnetic fields higher than 16 T (case of HTS dipole insert for Large Hadron Collider at CERN) or to increase the specific density stored in one SMES (Superconducting Magnetic Energy Storage, in the case of the SuperSMES ANR Project).Nevertheless the indisputable assets (critical temperature, critical magnetic field, mechanical stresses) brought by the use of High critical temperature superconductors like YBCO, used in superconducting magnets, require to solve some challenges. Their behavior is still badly understood, especially during the resistive transitions. To succeed in protecting these conductors we need a new reflection on protection schemes designed to avoid the thermal and mechanical damages. The answer to the question: 'Can we use those materials in the long run inside superconducting magnets?' is now inescapable.Some answers are given here. The use of the conductors is approached through various experimental studies to understand the material (electrical characterization and modeling of the critical surface) and to define the key stages of high critical temperature superconducting magnets manufacturing (work on the junctions between conductors and pancakes). This study led to the creation of two coils in order to identify the issues related to the use of YBCO tapes. A numerical thermo-electrical model of the high critical temperature superconductor has been developed and a numerical code based on the CEA software CASTEM (Finish Elements Model) allowed to study the resistive transition (or quench) behavior of those conductor and coil. The code has been

Superconducting magnet systems for MRI

International Nuclear Information System (INIS)

Hawksworth, D.G.

1988-01-01

MRI is the first large scale commercial application of superconductivity and has not achieved the status of a mature industry with an annual turnover in the magnet industry alone in excess of $150M. Conservative estimates put the investment of the medical industry in MRI as a whole at more than a billion dollars. In the nine years since shipment of the first superconducting whole body imaging magnets of 0.3 Tesla field the standard product of the industry has become a system of 1 meter bore and field strength 0.5 Tesla to 1.5 Tesla. In this paper the evolution of present day MRI magnets from small bore but high field spectrometer magnets is reviewed and the direction of future developments discussed

Quantum memory for superconducting qubits

International Nuclear Information System (INIS)

Pritchett, Emily J.; Geller, Michael R.

2005-01-01

Many protocols for quantum computation require a memory element to store qubits. We discuss the speed and accuracy with which quantum states prepared in a superconducting qubit can be stored in and later retrieved from an attached high-Q resonator. The memory fidelity depends on both the qubit-resonator coupling strength and the location of the state on the Bloch sphere. Our results show that a quantum memory demonstration should be possible with existing superconducting qubit designs, which would be an important milestone in solid-state quantum information processing. Although we specifically focus on a large-area, current-biased Josesphson-junction phase qubit coupled to the dilatational mode of a piezoelectric nanoelectromechanical disk resonator, many of our results will apply to other qubit-oscillator models

Academic training: Applied superconductivity

CERN Multimedia

2007-01-01

LECTURE SERIES 17, 18, 19 January from 11.00 to 12.00 hrs Council Room, Bldg 503 Applied Superconductivity : Theory, superconducting Materials and applications E. PALMIERI/INFN, Padova, Italy When hearing about persistent currents recirculating for several years in a superconducting loop without any appreciable decay, one realizes that we are dealing with a phenomenon which in nature is the closest known to the perpetual motion. Zero resistivity and perfect diamagnetism in Mercury at 4.2 K, the breakthrough during 75 years of several hundreds of superconducting materials, the revolution of the "liquid Nitrogen superconductivity"; the discovery of still a binary compound becoming superconducting at 40 K and the subsequent re-exploration of the already known superconducting materials: Nature discloses drop by drop its intimate secrets and nobody can exclude that the last final surprise must still come. After an overview of phenomenology and basic theory of superconductivity, the lectures for this a...

Electronic structure and superconductivity of FeSe-related superconductors.

Science.gov (United States)

Liu, Xu; Zhao, Lin; He, Shaolong; He, Junfeng; Liu, Defa; Mou, Daixiang; Shen, Bing; Hu, Yong; Huang, Jianwei; Zhou, X J

2015-05-13

FeSe superconductors and their related systems have attracted much attention in the study of iron-based superconductors owing to their simple crystal structure and peculiar electronic and physical properties. The bulk FeSe superconductor has a superconducting transition temperature (Tc) of ~8 K and it can be dramatically enhanced to 37 K at high pressure. On the other hand, its cousin system, FeTe, possesses a unique antiferromagnetic ground state but is non-superconducting. Substitution of Se with Te in the FeSe superconductor results in an enhancement of Tc up to 14.5 K and superconductivity can persist over a large composition range in the Fe(Se,Te) system. Intercalation of the FeSe superconductor leads to the discovery of the AxFe2-ySe2 (A = K, Cs and Tl) system that exhibits a Tc higher than 30 K and a unique electronic structure of the superconducting phase. A recent report of possible high temperature superconductivity in single-layer FeSe/SrTiO3 films with a Tc above 65 K has generated much excitement in the community. This pioneering work opens a door for interface superconductivity to explore for high Tc superconductors. The distinct electronic structure and superconducting gap, layer-dependent behavior and insulator-superconductor transition of the FeSe/SrTiO3 films provide critical information in understanding the superconductivity mechanism of iron-based superconductors. In this paper, we present a brief review of the investigation of the electronic structure and superconductivity of the FeSe superconductor and related systems, with a particular focus on the FeSe films.

Superconductivity

International Nuclear Information System (INIS)

2007-01-01

During 2007, a large amount of the work was centred on the ITER project and related tasks. The activities based on low-temperature superconducting (LTS) materials included the manufacture and qualification of ITER full-size conductors under relevant operating conditions, the design of conductors and magnets for the JT-60SA tokamak and the manufacture of the conductors for the European dipole facility. A preliminary study was also performed to develop a new test facility at ENEA in order to test long-length ITER or DEMO full-size conductors. Several studies on different superconducting materials were also started to create a more complete database of superconductor properties, and also for use in magnet design. In this context, an extensive measurement campaign on transport and magnetic properties was carried out on commercially available NbTi strands. Work was started on characterising MgB 2 wire and bulk samples to optimise their performance. In addition, an intense experimental study was started to clarify the effect of mechanical loads on the transport properties of multi-filamentary Nb 3 Sn strands with twisted or untwisted superconducting filaments. The experimental activity on high-temperature superconducting (HTS) materials was mainly focussed on the development and characterisation of YBa 2 Cu 3 O 7-X (YBCO) based coated conductors. Several characteristics regarding YBCO deposition, current transport performance and tape manufacture were investigated. In the framework of chemical approaches for YBCO film growth, a new method, developed in collaboration with the Technical University of Cluj-Napoca (TUCN), Romania, was studied to obtain YBCO film via chemical solution deposition, which modifies the well-assessed metallic organic deposition trifluoroacetate (MOD-TFA) approach. The results are promising in terms of critical current and film thickness values. YBCO properties in films with artificially added pinning sites were characterised in collaboration with

Summary of existing superconducting magnet experience and its relevance to the safety of fusion magnet

International Nuclear Information System (INIS)

Hsieh, S.Y.; Allinger, J.; Danby, G.; Keane, J.; Powell, J.; Prodell, A.

1975-01-01

A comprehensive summary of experience with over twenty superconducting magnet systems has been collected through visits to and discussions about existing facilities including, for example, the bubble chamber magnets at Brookhaven National Laboratory, Argonne National Laboratory and Fermi National Accelerator Laboratory, and the large superconducting spectrometer at Stanford Linear Accelerator Center. This summary includes data relating to parameters of these magnets, magnet protection methods, and operating experiences. The information received is organized and presented in the context of its relevance to the safe operation of future, very large superconducting magnet systems for fusion power plants

CERN tests largest superconducting solenoid magnet

CERN Multimedia

2006-01-01

"CERN's Compacts Muon Solenoid (CMS) - the world's largest superconducting solenoid magnet - has reached full field in testing. The instrument is part of the proton-proton Large Hadron Collider (LHC) project, located in a giant subterranean chamber at Cessy on the Franco-Swiss border." (1 page)

The association of foot arch posture and prior history of shoulder or elbow surgery in elite-level baseball pitchers.

Science.gov (United States)

Feigenbaum, Luis A; Roach, Kathryn E; Kaplan, Lee D; Lesniak, Bryson; Cunningham, Sean

2013-11-01

Case-control. The specific aim of this study was to examine the association between abnormal foot arch postures and a history of shoulder or elbow surgery in baseball pitchers. Pitching a baseball generates forces throughout the musculoskeletal structures of the upper and lower limbs. Structures such as the longitudinal arch of the foot are adaptable to stresses over time. Repeated pitching-related stresses may contribute to acquiring abnormal foot arch postures. Inversely, congenitally abnormal foot arch posture may lead to altered stresses of the upper limb during pitching. A convenience sample of 77 pitchers was recruited from a Division I university team and a professional baseball franchise. Subjects who had a history of shoulder or elbow surgery to the pitching arm were classified as cases. Subjects who met the criteria for classification of pes planus or pes cavus based on longitudinal arch angle were classified as having abnormal foot arch posture. Odds ratios were calculated to examine the association between abnormal foot arch posture and pitching-arm injury requiring surgery. Twenty-three subjects were classified as cases. The odds of being a case were 3.4 (95% confidence interval: 1.2, 9.6; P = .02) times greater for subjects with abnormal foot arch posture and 2.9 (95% confidence interval: 1.0, 8.1; P = .04) times greater for subjects with abnormal foot posture on the lunge leg. Abnormal foot arch posture and a surgical history in the pitching shoulder or elbow may be associated. Because the foot and its arches are adaptable and change over time, the pathomechanics of this association should be further explored.

Flux free growth of large FeSe1/2Te1/2 superconducting single crystals by an easy high temperature melt and slow cooling method

Directory of Open Access Journals (Sweden)

P. K. Maheshwari

2015-09-01

Full Text Available We report successful growth of flux free large single crystals of superconducting FeSe1/2Te1/2 with typical dimensions of up to few cm. The AC and DC magnetic measurements revealed the superconducting transition temperature (Tc value of around 11.5K and the isothermal MH showed typical type-II superconducting behavior. The lower critical field (Hc1 being estimated by measuring the low field isothermal magnetization in superconducting regime is found to be above 200Oe at 0K. The temperature dependent electrical resistivity ρ(T  showed the Tc (onset to be 14K and the Tc(ρ = 0 at 11.5K. The electrical resistivity under various magnetic fields i.e., ρ(TH for H//ab and H//c demonstrated the difference in the width of Tc with applied field of 14Tesla to be nearly 2K, confirming the anisotropic nature of superconductivity. The upper critical and irreversibility fields at absolute zero temperature i.e., Hc2(0 and Hirr(0 being determined by the conventional one-band Werthamer–Helfand–Hohenberg (WHH equation for the criteria of normal state resistivity (ρn falling to 90% (onset, and 10% (offset is 76.9Tesla, and 37.45Tesla respectively, for H//c and 135.4Tesla, and 71.41Tesla respectively, for H//ab. The coherence length at the zero temperature is estimated to be above 20Å ´ by using the Ginsburg-Landau theory. The activation energy for the FeSe1/2Te1/2 in both directions H//c and H//ab is determined by using Thermally Activation Flux Flow (TAFF model.

Out-of-Hospital Cardiac Arrests During the Japanese Professional Baseball Championship Series.

Science.gov (United States)

Onozuka, Daisuke; Hagihara, Akihito

2018-03-14

Because the Japan Professional Baseball Championship Series (Japan Series) is a stressful sports event, it is possible that watching Japan Series matches may increase the risk of cardiovascular events. Therefore, we investigated the potential association between the Japan Series and the incidence of out-of-hospital cardiac arrest (OHCA) events. National registry data for all cases of OHCA between 2005 and 2014 from 47 prefectures of Japan were obtained. We used a time-stratified case-crossover design with a conditional Poisson regression model to compare OHCA events during the Japan Series with those events that occurred during the periods except for dates of the Japan Series. The estimated associations for each prefecture were pooled at the nationwide level using a random-effects meta-analysis. In total, 666,020 OHCAs of presumed cardiac origin were reported during the study period. On days of Japan Series matches, the pooled relative risk of OHCA was 1.033 (95% confidence interval 1.012 to 1.055; p = 0.002; I 2  = 3.5%, P for heterogeneity = 0.405). Stratified analyses by gender revealed that the substantial increase in OHCA during the events was observed for men, whereas we found no significant increase for women. We also found a considerable rise in OHCA among patients aged ≥65 years; however, there was no significant evidence of increased risk in those aged 18 to 64 years. In conclusion, stressful baseball match is associated with an increased risk of OHCA. Prevention measures for severe emotional stress-related OHCA should be implemented, particularly for elderly men. Copyright © 2018 Elsevier Inc. All rights reserved.

Superconductivity - applications

International Nuclear Information System (INIS)

The paper deals with the following subjects: 1) Electronics and high-frequency technology, 2) Superconductors for energy technology, 3) Superconducting magnets and their applications, 4) Electric machinery, 5) Superconducting cables. (WBU) [de

A Course on Applied Superconductivity Shared by Four Departments

DEFF Research Database (Denmark)

Jensen, Bogi Bech; Abrahamsen, Asger Bech; Sørensen, Mads Peter

2011-01-01

superconductivity the focus was on an application, which could benefit from using superconductors. The application used in this course was superconducting generators for direct drive wind turbines. As part of the course the students built a small-scale superconducting machine and set up finite element models...... of that machine as well as large-scale wind turbine generators with superconductors and also permanent magnet generators. The course was assessed by a student conference contribution and reports from the students. The quality of the course was evaluated by interviewing the students after the course had finished....... The students were very pleased with the course and gave suggestions of how the course could be improved further....

Advances in superconducting cyclotrons at MSU

International Nuclear Information System (INIS)

Blosser, H.; Antaya, T.; Au, R.

1987-01-01

Intensive work on superconducting cyclotrons began at MSU in late 1973 (a brief earlier study had occurred in the early 1960's) and continues vigorously at present. One large cyclotron, the ''K500'', has been operating for a number of years, a second, the ''K800'', is nearing completion, the first operating tests of its magnet having occurred at the time of the previous conference, and a third, the ''medical cyclotron'', is now also nearing completion with first operation of its magnet expected just after the present conference. These cyclotrons like other superconducting cyclotrons are all dramatically smaller than comparable room temperature machines; overall weight is typically about 1/20th of that of room temperature cyclotrons of the same energy. This large reduction in the quantities of materials is partially offset by added complexity, but finally, a net overall cost savings of 50 to 70 % typically results; as a consequence the superconducting cyclotron is widely viewed as the cyclotron of the future. The thirteen years of experience at MSU involving three of these cyclotrons, together with much important work at other laboratories, gives a rather clear view of the advantages and disadvantages of various design approaches including by now a rather significant period of long term evaluation. This paper reviews highlights of this program. (author)

Superconductivity for Large Scale Wind Turbines

Energy Technology Data Exchange (ETDEWEB)

R. Fair; W. Stautner; M. Douglass; R. Rajput-Ghoshal; M. Moscinski; P. Riley; D. Wagner; J. Kim; S. Hou; F. Lopez; K. Haran; J. Bray; T. Laskaris; J. Rochford; R. Duckworth

2012-10-12

A conceptual design has been completed for a 10MW superconducting direct drive wind turbine generator employing low temperature superconductors for the field winding. Key technology building blocks from the GE Wind and GE Healthcare businesses have been transferred across to the design of this concept machine. Wherever possible, conventional technology and production techniques have been used in order to support the case for commercialization of such a machine. Appendices A and B provide further details of the layout of the machine and the complete specification table for the concept design. Phase 1 of the program has allowed us to understand the trade-offs between the various sub-systems of such a generator and its integration with a wind turbine. A Failure Modes and Effects Analysis (FMEA) and a Technology Readiness Level (TRL) analysis have been completed resulting in the identification of high risk components within the design. The design has been analyzed from a commercial and economic point of view and Cost of Energy (COE) calculations have been carried out with the potential to reduce COE by up to 18% when compared with a permanent magnet direct drive 5MW baseline machine, resulting in a potential COE of 0.075 $/kWh. Finally, a top-level commercialization plan has been proposed to enable this technology to be transitioned to full volume production. The main body of this report will present the design processes employed and the main findings and conclusions.

Progress on axicell MFTF-B superconducting magnet systems

International Nuclear Information System (INIS)

Wang, S.T.; Kozman, T.A.; Hanson, C.L.; Shimer, D.W.; VanSant, J.H.; Zbasnik, J.

1983-01-01

Since the entire Mirror Fusion Test Facility (MFTF-B) Magnet System was reconfigured from the original A-cell to an axicell design, much progress has been made on the design, fabrication, and installation planning. The axicell MFTF-B magnet array consists of a total of 26 large superconducting main coils. This paper provides an engineering overview of the progress of these coils. Recent studies on the effects of field errors on the plasma at the recircularizing region (transition coils) show that small field errors will generate large displacements of the field lines. These field errors might enhance radial electron heat transport and deteriorate the plasma confinement. Therefore, 16 superconducting trim coils have been designed to correct the coil misalignments. Progress of the trim coils are reported also

Basic Study of Superconductive Actuator

OpenAIRE

涌井, 和也; 荻原, 宏康

2000-01-01

There are two kinds of electromagnetic propulsion ships : a superconductive electromagnetic propulsion ship and a superconductive electricity propulsion ship. A superconductive electromagnetic propulsion ship uses the electromagnetic force (Lorenz force) by the interaction between a magnetic field and a electric current. On the other hand, a superconductive electricity propulsion ship uses screws driven by a superconductive motor. A superconductive propulsion ship technique has the merits of ...

100 years of superconductivity

CERN Document Server

Rogalla, Horst

2011-01-01

Even a hundred years after its discovery, superconductivity continues to bring us new surprises, from superconducting magnets used in MRI to quantum detectors in electronics. 100 Years of Superconductivity presents a comprehensive collection of topics on nearly all the subdisciplines of superconductivity. Tracing the historical developments in superconductivity, the book includes contributions from many pioneers who are responsible for important steps forward in the field.The text first discusses interesting stories of the discovery and gradual progress of theory and experimentation. Emphasizi

Superconducting current in a bisoliton superconductivity model

International Nuclear Information System (INIS)

Ermakov, V.N.; Kruchinin, S.P.; Ponezha, E.A.

1991-01-01

It is shown that the transition into a superconducting state with the current which is described by a bisoliton superconductivity model is accompanied by the deformation of the spectrum of one-particle states of the current carriers. The deformation value is proportional to the conducting current force. The residuaby resistance in such state is absent

Coexistence of magnetism and superconductivity in the hole doped FeAs-based superconducting compound

International Nuclear Information System (INIS)

Lu, T.P.; Wu, C.C.; Chou, W.H.; Lan, M.D.

2010-01-01

The magnetic and superconducting properties of the Sm-doped FeAs-based superconducting compound were investigated under wide ranges of temperature and magnetic field. After the systematical magnetic ion substitution, the superconducting transition temperature decreases with increasing magnetic moment. The hysteresis loop of the La 0.87-x Sm x Sr 0.13 FeAsO sample shows a superconducting hysteresis and a paramagnetic background signal. The paramagnetic signal is mainly attributed to the Sm moments. The experiment demonstrates that the coexistence of magnetism and superconductivity in the hole doped FeAs-based superconducting compounds is possible. Unlike the electron doped FeAs-based superconducting compounds SmFeAsOF, the hole doped superconductivity is degraded by the substitution of La by Sm. The hole-doped and electron-doped sides are not symmetric.

STS-95 Payload Specialist Glenn greets baseball legend Williams following a parade in Cocoa Beach

Science.gov (United States)

1998-01-01

STS-95 Payload Specialist John H. Glenn Jr. (left) greets baseball legend Ted Williams at a reception at the Double Tree Oceanfront Hotel following a parade down State Road A1A in nearby Cocoa Beach. Organizers of the parade included the Cocoa Beach Area Chamber of Commerce, the Brevard County Tourist Development Council, and the cities of Cape Canaveral and Cocoa Beach. The parade is reminiscent of those held after missions during the Mercury Program.

Safety and reliability in superconducting MHD magnets

International Nuclear Information System (INIS)

Laverick, C.; Powell, J.; Hsieh, S.; Reich, M.; Botts, T.; Prodell, A.

1979-07-01

This compilation adapts studies on safety and reliability in fusion magnets to similar problems in superconducting MHD magnets. MHD base load magnet requirements have been identified from recent Francis Bitter National Laboratory reports and that of other contracts. Information relevant to this subject in recent base load magnet design reports for AVCO - Everett Research Laboratories and Magnetic Corporation of America is included together with some viewpoints from a BNL workshop on structural analysis needed for superconducting coils in magnetic fusion energy. A summary of design codes used in large bubble chamber magnet design is also included

Superconducting magnet systems in EPR designs

International Nuclear Information System (INIS)

Knobloch, A.F.

1976-10-01

Tokamak experiments have reached a stage where large scale application of superconductors can be envisaged for machines becoming operational within the next decade. Existing designs for future devices already indicate some of the tasks and problems associated with large superconducting magnet systems. Using this information the coming magnet system requirements are summarized, some design considerations given and in conclusion a brief survey describes already existing Tokamak magnet development programs. (orig.) [de

Prototype superconducting magnet for the FFAG accelerator

International Nuclear Information System (INIS)

Obana, T.; Ogitsu, T.; Yamamoto, A.; Yoshimoto, M.; Mori, Y.; Fujii, T.; Iwasa, M.; Orikasa, T.

2006-01-01

A study of a superconducting magnet for the Fixed Field Alternating Gradient (FFAG) accelerator has been performed. The FFAG accelerator requires static magnetic field, and it is suitable for superconducting magnet applications, because problems associated with time varying magnetic field such as eddy current loss can be eliminated. The superconducting magnet, which can generate high magnetic field, is possible to realize a higher beam energy with a given accelerator size or the size to be smaller for a given beam energy. The FFAG accelerator magnet is demanded to have a complicated nonlinear magnetic field with high accuracy. As a first prototype superconducting coil, the coil configuration which consists of left-right asymmetric cross-section and large aperture has been designed. The prototype coil has been successfully developed by using a 6-axis Computer Numerical Control (CNC) winding machine. The magnetic field of the prototype coil has been demonstrated in warm measurement. As a consequence, the technical feasibility has been verified with the prototype coil development and the performance test. In addition, the technology components developed in the prototype coil have a possibility to transfer to a fusion magnet

Structural support system for a superconducting magnet coil

International Nuclear Information System (INIS)

Meuser, R.B.

1977-01-01

The purpose of the ESCAR (Experimental Superconducting Accelerator Ring) project, now under way at the Lawrence Berkeley Laboratory, is to gather data and experience in the design and operation of a relatively small synchrotron employing superconducting magnets. Such data are essential to ensure that the design of future large accelerators may proceed in a knowledgeable and responsible manner. One of the many engineering problems associated with a superconducting magnet is the design of the coil suspension system. The coil, maintained at the temperature of liquid helium, must be held rigidly by a structure that does not conduct too much heat into the liquid helium system. The suspension system used on the ESCAR magnets is described. Topics covered include the coil support system requirements, ESCAR magnet support system, and operating experience

Future of IT, PT and superconductivity technology

Science.gov (United States)

Tanaka, Shoji

2003-10-01

Recently the Information Technology is developing very rapidly and the total traffic on the Internet is increasing dramatically. The numerous equipments connected to the Internet must be operated at very high-speed and the electricity consumed in the Internet is also increasing. Superconductivity devices of very high-speed and very low power consumption must be introduced. These superconducting devices will play very important roles in the future information society. Coated conductors will be used to generate extremely high magnetic fields of beyond 20 T at low temperatures. At the liquid nitrogen temperature they can find many applications in a wide range of Power Technology and other industries, since we have already large critical current and brilliant magnetic field dependences in some prototypes of coated conductors. It is becoming certain that the market for the superconductivity technology will be opened between the years of 2005 and 2010.

Decay and Snapback in Superconducting Accelerator Magnets

CERN Document Server

Haverkamp, M

2003-01-01

This thesis deals with the explanation and compensation of the effects 'decay' and 'snapback' in superconducting accelerator magnets, in particular in those used in the new Large Hardron Collider at CERN. During periods of constant magnet excitation, as for example during the injection of particles in the storage ring, the magnetic field in superconducting accelerator magnets shows a decay behavior. As soon as the particles are accelerated, the magnets are ramped, and the magnetic field 'snaps back' to the original hysteresis curve. Decay and snapback affect the beam in the machine and have tobe compensated precisely in order to avoid losses of particles. The research presented in this thesis is a step towards a better understanding of 'decay' and 'snapback' in superconducting particle accelerators. The thesis provides tools for the prediction and compensation of both effects in the magnets, and for the analysis of correlations between different magnet parameters.

Lower extremity muscle activation during baseball pitching.

Science.gov (United States)

Campbell, Brian M; Stodden, David F; Nixon, Megan K

2010-04-01

The purpose of this study was to investigate muscle activation levels of select lower extremity muscles during the pitching motion. Bilateral surface electromyography data on 5 lower extremity muscles (biceps femoris, rectus femoris, gluteus maximus, vastus medialis, and gastrocnemius) were collected on 11 highly skilled baseball pitchers and compared with individual maximal voluntary isometric contraction (MVIC) data. The pitching motion was divided into 4 distinct phases: phase 1, initiation of pitching motion to maximum stride leg knee height; phase 2, maximum stride leg knee height to stride foot contact (SFC); phase 3, SFC to ball release; and phase 4, ball release to 0.5 seconds after ball release (follow-through). Results indicated that trail leg musculature elicited moderate to high activity levels during phases 2 and 3 (38-172% of MVIC). Muscle activity levels of the stride leg were moderate to high during phases 2-4 (23-170% of MVIC). These data indicate a high demand for lower extremity strength and endurance. Specifically, coaches should incorporate unilateral and bilateral lower extremity exercises for strength improvement or maintenance and to facilitate dynamic stabilization of the lower extremities during the pitching motion.

A sourcebook of titanium alloy superconductivity

CERN Document Server

Collings, E W

1983-01-01

In less than two decades the concept of supercon­ In every field of science there are one or two ductivity has been transformed from a laboratory individuals whose dedication, combined with an innate curiosity to usable large-scale applications. In the understanding, permits them to be able to grasp, late 1960's the concept of filamentary stabilization condense, and explain to the rest of us what that released the usefulness of zero resistance into the field is all about. For the field of titanium alloy marketplace, and the economic forces that drive tech­ superconductivity, such an individual is Ted Collings. nology soon focused on niobium-titanium alloys. They His background as a metallurgist has perhaps given him are ductile and thus fabricable into practical super­ a distinct advantage in understanding superconduc­ conducting wires that have the critical currents and tivity in titanium alloys because the optimization of fields necessary for large-scale devices. More than superconducting parameters in ...

A large superconducting accelerator project. International linear collider (ILC). Introduction

International Nuclear Information System (INIS)

Yamamoto, Akira

2013-01-01

The international linear collider (ILC) is proposed as the next-energy-frontier particle accelerator anticipated to be realized through global cooperation. The ILC accelerator is composed of a pair of electron and positron linear accelerators to realize head-on collision with a center-of-mass energy of 500 (250+250) GeV. It is based on superconducting radio-frequency (SCRF) technology, and the R and D and technical design have progressed in the technical design phase since 2007, and the technical design report (TDR) reached completion in 2012. This report reviews the ILC general design and technology. (author)

Magnetostatics of anisotropic superconducting ellipsoid

International Nuclear Information System (INIS)

Saif, A.G.

1987-09-01

The magnetization and the magnetic field distribution inside (outside) an anisotropic type II superconducting ellipsoid, with filamentary structure, is formulated. We have shown that the magnetic field in this case is different from that of the general anisotropic one. The nucleations of the flux lines for specimens with large demagnetization factors are theoretically studied. We have shown that the nucleations of the flux lines, for specimens with large demagnetization factor, appears at a field larger than that of ellipsoidal shape. (author). 15 refs

Superconducting cavity development at RRCAT

International Nuclear Information System (INIS)

Joshi, S.C.

2015-01-01

Raja Ramanna Centre for Advanced Technology (RRCAT), Indore pursuing a program on 'R and D Activities for High Energy Proton Linac based Spallation Neutron Source'. Spallation neutron source (SNS) facility will provide high flux pulse neutrons for research in the areas of condensed matter physics, materials science, chemistry, biology and engineering. This will complement the existing synchrotron light source facility, INDUS-2 at RRCAT and reactor based neutron facilities at BARC. RRCAT is also participating in approved mega project on 'Physics and Advanced Technology for High Intensity Proton Accelerator' to support activities of Indian Institutions - Fermilab Collaboration (IIFC). The SNS facility will have a 1 GeV superconducting proton injector linac and 1 GeV accumulator ring. The linac will comprise of large number of superconducting radio-frequency (SCRF) cavities operating at different RF frequencies housed in suitable cryomodules. Thus, an extensive SCRF cavity infrastructure setup is being established. In addition, a scientific and technical expertise are also being developed for fabrication, processing and testing of the SCRF cavities for series production. The paper presents the status of superconducting cavity development at RRCAT

High-current applications of superconductivity

International Nuclear Information System (INIS)

Komarek, P.

1995-01-01

The following topics were dealt with: superconducting materials, design principles of superconducting magnets, magnets for research and engineering, superconductivity for power engineering, superconductivity in nuclear fusion technology, economical considerations

The effects of forearm fatigue on baseball fastball pitching, with implications about elbow injury.

Science.gov (United States)

Wang, Lin-Hwa; Lo, Kuo-Cheng; Jou, I-Ming; Kuo, Li-Chieh; Tai, Ta-Wei; Su, Fong-Chin

2016-01-01

This study investigated the contribution of flexor muscles to the forearm through fatigue; therefore, the differences in forearm mechanisms on the pitching motion in fastball were analysed. Fifteen baseball pitchers were included in this study. Ultrasonographical examination of participants' ulnar nerve in the cubital tunnel with the elbow extended and at 45°, 90° and 120° of flexion was carried. A three-dimensional motion analysis system with 14 reflective markers attached on participants was used for motion data collection. The electromyography system was applied over the flexor carpi ulnaris, flexor carpi radialis and extensor carpi radialis muscles of the dominant arm. Flexor carpi ulnaris muscle activity showed a significant difference during the acceleration phase, with a peak value during fastball post-fatigue (P = 0.02). Significant differences in the distance between ulnar nerve and medial condyle on throwing arm and non-throwing arm were observed as the distance increased with the elbow movement from 0° to 120° of flexion (P = 0.01). The significant increase of the flexor carpi ulnaris muscle activity might be responsible for maintaining the stability of the wrist joint. The increased diameter might compress the ulnar nerve and cause several pathological changes. Therefore, fatigue in baseball pitchers still poses a threat to the ulnar nerve because the flexor carpi ulnaris and flexor carpi radialis all originate from the medial side of the elbow, and the swelling tendons after fatigue might be a key point.

Safety and stability in superconducting magnets

International Nuclear Information System (INIS)

Herring, J.S.

1989-01-01

The increasing size and field of superconducting magnets required for new applications result in significant stored energy and magnetic forces. The use of superconducting magnets near humans has resulted in standards for limiting occupational exposures to magnetic field. While these standards are unofficial, they have been widely adopted. In addition, development of large magnet sets for the fusion program and for the MHD program has led to experiments on the behavior of shorted and arcing coils under transient conditions. In combination with various code development efforts, these experiments, in the US and Europe, are resulting in criteria for the design of stable coils which can safely discharge their stored energy. 22 refs., 6 tabs

Superconducting magnetic shields for neutral beam injectors. Final report

International Nuclear Information System (INIS)

1985-04-01

Large high energy deuterium neutral beams which must be made from negative ions require extensive magnetic shielding against the intense fringe fields surrounding a magnetic fusion power plant. The feasibility of shielding by multilayer sheets of copper-superconducting laminated material was investigated. It was found that, if necessary fabrication techniques are developed, intrinsically stable type II superconductors will be able to shield against the magnetic fields of the fusion reactors. Among the immediate benefits of this research is better magnetic shields for neutral beam injectors in support of DOE's fusion program. Another application may be in the space vehicles, where difficulties in transporting heavy μ-metal sections may make a comparatively light superconducting shield attractive. Also, as high-field superconducting magnets find widespread applications, the need for high-intensity magnetic shielding will increase. As a result, the commercial market for the magnetic shields should expand along with the market for superconducting magnets

Laser activated superconducting switch

International Nuclear Information System (INIS)

Wolf, A.A.

1976-01-01

A superconducting switch or bistable device is described consisting of a superconductor in a cryogen maintaining a temperature just below the transition temperature, having a window of the proper optical frequency band for passing a laser beam which may impinge on the superconductor when desired. The frequency of the laser is equal to or greater than the optical absorption frequency of the superconducting material and is consistent with the ratio of the gap energy of the switch material to Planck's constant, to cause depairing of electrons, and thereby normalize the superconductor. Some embodiments comprise first and second superconducting metals. Other embodiments feature the two superconducting metals separated by a thin film insulator through which the superconducting electrons tunnel during superconductivity

Electronic Systems for the Protection of Superconducting Elements in the LHC

CERN Document Server

Denz, R

2006-01-01

The Large Hadron Collider LHC, currently under construction at CERN, will incorporate an unprecedented number of superconducting magnets, busbars and current leads. As most of these elements depend on active protection in case of a transition from the superconducting to the resistive state, the so-called quench, a protection system based on modern, state of the art electronics has been developed.

Electrical supply for MFTF-B superconducting magnet system

International Nuclear Information System (INIS)

Shimer, D.W.; Owen, E.W.

1985-01-01

The MFTF-B magnet system consists of 42 superconducting magnets which must operate continuously for long periods of time. The magnet power supply system is designed to meet the operational requirements of accuracy, flexibility, and reliability. The superconducting magnets require a protection system to protect against critical magnet faults of quench, current lead overtemperature, and overcurrent. The protection system is complex because of the large number of magnets, the strong coupling between magnets, and the high reliability requirement. This paper describes the power circuits and the components used in the design

AC loss in superconducting tapes and cables

NARCIS (Netherlands)

Oomen, M.P.

2000-01-01

The present study discusses the AC loss in high-temperature superconductors. Superconducting materials with a relatively high critical temperature were discovered in 1986. They are presently developed for use in large-scale power-engineering devices such as power-transmission cables, transformers

Superconducting linac

International Nuclear Information System (INIS)

Bollinger, L.M.; Shepard, K.W.; Wangler, T.P.

1978-01-01

This project has two goals: to design, build, and test a small superconducting linac to serve as an energy booster for heavy ions from an FN tandem electrostatic accelerator, and to investigate various aspects of superconducting rf technology. The main design features of the booster are described, a status report on various components (resonators, rf control system, linac control system, cryostats, buncher) is given, and plans for the near future are outlined. Investigations of superconducting-linac technology concern studies on materials and fabrication techniques, resonator diagnostic techniques, rf-phase control, beam dynamics computer programs, asymmetry in accelerating field, and surface-treatment techniques. The overall layout of the to-be-proposed ATLAS, the Argonne Tandem-Linac Accelerator System, is shown; the ATLAS would use superconducting technology to produce beams of 5 to 25 MeV/A. 6 figures

Superconductivity and electron microscopy

International Nuclear Information System (INIS)

Hawkes, P.W.; Valdre, U.

1977-01-01

In this review article, two aspects of the role of superconductivity in electron microscopy are examined: (i) the development of superconducting devices (mainly lenses) and their incorporation in electron microscopes; (ii) the development of electron microscope techniques for studying fundamental and technological problems associated with superconductivity. The first part opens with a brief account of the relevant properties of conventional lenses, after which the various types of superconducting lenses are described and their properties compared. The relative merits and inconveniences of superconducting and conventional lenses are examined, particular attention being paid to the spherical and chromatic aberration coefficients at accelerating voltages above a megavolt. This part closes with a survey of the various microscope designs that have been built or proposed, incorporating superconducting components. In the second part, some methods that have been or might be used in the study of superconductivity in the electron microscope are described. A brief account of the types of application for which they are suitable is given. (author)

Superconductivity in transition metals.

Science.gov (United States)

Slocombe, Daniel R; Kuznetsov, Vladimir L; Grochala, Wojciech; Williams, Robert J P; Edwards, Peter P

2015-03-13

A qualitative account of the occurrence and magnitude of superconductivity in the transition metals is presented, with a primary emphasis on elements of the first row. Correlations of the important parameters of the Bardeen-Cooper-Schrieffer theory of superconductivity are highlighted with respect to the number of d-shell electrons per atom of the transition elements. The relation between the systematics of superconductivity in the transition metals and the periodic table high-lights the importance of short-range or chemical bonding on the remarkable natural phenomenon of superconductivity in the chemical elements. A relationship between superconductivity and lattice instability appears naturally as a balance and competition between localized covalent bonding and so-called broken covalency, which favours d-electron delocalization and superconductivity. In this manner, the systematics of superconductivity and various other physical properties of the transition elements are related and unified. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Superconducting-electromagnetic hybrid bearing using YBCO bulk blocks for passive axial levitation

Science.gov (United States)

Nicolsky, R.; de Andrade, R., Jr.; Ripper, A.; David, D. F. B.; Santisteban, J. A.; Stephan, R. M.; Gawalek, W.; Habisreuther, T.; Strasser, T.

2000-06-01

A superconducting/electromagnetic hybrid bearing has been designed using active radial electromagnetic positioning and a superconducting passive axial levitator. This bearing has been tested for an induction machine with a vertical shaft. The prototype was conceived as a four-pole, two-phase induction machine using specially designed stator windings for delivering torque and radial positioning simultaneously. The radial bearing uses four eddy-current sensors, displaced 90° from each other, for measuring the shaft position and a PID control system for feeding back the currents. The stator windings have been adapted from the ones of a standard induction motor. The superconducting axial bearing has been assembled with commercial NdFeB permanent magnets and a set of seven top-seeded-melt-textured YBCO large-grain cylindrical blocks. The bearing set-up was previously simulated by a finite element method for different permanent magnet-superconductor block configurations. The stiffness of the superconducting axial bearing has been investigated by measuring by a dynamic method the vertical and transversal elastic constants for different field cooling processes. The resulting elastic constants show a linear dependence on the air gap, i.e. the clearance between the permanent magnet assembly and the set of superconducting large-grain blocks, which is dependent on cooling distance.

Magnetic levitation force between a superconducting bulk magnet and a permanent magnet

International Nuclear Information System (INIS)

Wang, J J; He, C Y; Meng, L F; Li, C; Han, R S; Gao, Z X

2003-01-01

The current density J(ρ, z) in a disc-shaped superconducting bulk magnet and the magnetic levitation force F SBM z exerted on the superconducting bulk magnet by a cylindrical permanent magnet are calculated from first principles. The effect of the superconducting parameters of the superconducting bulk is taken into account by assuming the voltage-current law E = E c (J/J c ) n and the material law B = μ 0 H. The magnetic levitation force F SBM z is dominated by the remnant current density J' 2 (ρ, z), which is induced by switching off the applied magnetizing field. High critical current density and flux creep exponent may increase the magnetic levitation force F SBM z . Large volume and high aspect ratio of the superconducting bulk can further enhance the magnetic levitation force F SBM z

Linear arrangement of metallic and superconducting defects in a thin superconducting sample

International Nuclear Information System (INIS)

Barba-Ortega, J.; Sardella, Edson; Albino Aguiar, J.

2013-01-01

Highlights: • We study the influence of superconducting and metallic defects on the vortex configurations in a thin mesoscopic disk. • We found that the vortex–defect interaction leads to interesting vortex configurations. • The first vortex entry is always (never) found sitting on the metallic (superconducting) defect position. -- Abstract: The vortex matter in a superconducting disk with a linear configuration of metallic and superconducting defects is studied. Effects associated to the pinning (anti-pinning) force of the metallic (superconducting) defect on the vortex configuration and on the thermodynamic critical fields are analyzed in the framework of the Ginzburg Landau theory. We calculate the loop of the magnetization, vorticity and free energy curves as a function of the magnetic field for a thin disk. Due to vortex–defect attraction for a metallic defect (repulsion for a superconducting defect), the vortices always (never) are found to be sitting on the defect position

Brand Equity, Efficiency and Valuation of Professional Sports Franchises: The Case of Major League Baseball

OpenAIRE

Srinivas K Reddy; Antonie Stam; Per J Agrell

2015-01-01

Values of professional sports franchises have outpaced even investment returns in recent bull markets. Financial World found the value of professional teams like the Dallas Cowboys, Miami Dolphins and the NY Yankees to exceed $200 million each. In 1996, the average estimated value of Major League Baseball (MLB) teams was $134 million, and most showed double-digit growth in value, although 13 of the 26 teams were in the red. Our research proposes a model to determine the value of a professiona...

Conceptual design of a superconducting solenoid for a magnetic SSC [Superconducting Super Collider] detector

International Nuclear Information System (INIS)

Fast, R.W.; Grimson, J.H.; Kephart, R.D.; Krebs, H.J.; Stone, M.E.; Theriot, D.; Wands, R.H.

1988-07-01

The conceptual design of a large superconducting solenoid suitable for a magnetic detector at the Superconducting Super Collider (SSC) has begun at Fermilab. The magnet will provide a magnetic field of 2 T over a volume 8 m in diameter by 16 m long. The particle-physics calorimetry will be inside the field volume and so the coil will be bath cooled and cryostable; the vessels will be stainless steel. Predictibility of performance and the ability to safely negotiate all probable failure modes, including a quench, are important items of the design philosophy. Although the magnet is considerably larger than existing solenoids of this type and although many issues of manufacturability, transportability and cost have not been completely addressed, our conceptual design has convinced us that this magnet is a reasonable extrapolation of present technology. 2 figs., 2 tabs

Superconducting state mechanisms and properties

CERN Document Server

Kresin, Vladimir Z; Wolf, Stuart A

2014-01-01

'Superconducting State' provides a very detailed theoretical treatment of the key mechanisms of superconductivity, including the current state of the art (phonons, magnons, and plasmons). A very complete description is given of the electron-phonon mechanism responsible for superconductivity in the majority of superconducting systems, and the history of its development, as well as a detailed description of the key experimental techniques used to study the superconducting state and determine the mechanisms. In addition, there are chapters describing the discovery and properties of the key superconducting compounds that are of the most interest for science, and applications including a special chapter on the cuprate superconductors. It provides detailed treatments of some very novel aspects of superconductivity, including multiple bands (gaps), the "pseudogap" state, novel isotope effects beyond BCS, and induced superconductivity.

Achieved capability of the superconducting magnet system for the large helical device

International Nuclear Information System (INIS)

Satow, T.; Imagawa, S.; Yanagi, N.

2001-01-01

The Large Helical Device (LHD) is a plasma physics experimental device with a magnetic stored energy of 960 MJ, consisting of two sc (superconducting) helical coils and six sc poloidal coils. The trial operation and the first plasma discharge of the eight-year Phase I project for LHD were finished on 31 March 1998 as initially planned. The second experimental campaign was conducted by additional heating using two NBI devices. The third campaign started in June 1999 and was finished in January 2000. Many plasma heating tests up to a plasma field of 2.90 T were carried out. Major test results on the sc magnet system for LHD are as follows: (1) The LHD cryogenic system succeeded in 13,400-hour operation and proved its high reliability. (2) A central field of 2.91 T at a radius of 3.60 m was achieved at an H-I current of 11.08 kA, H-M current of 11.83 kA and an H-O current of 12.02 kA. (3) All six poloidal coils were excited stably. (4) Nine flexible sc bus-lines with a total length of 497 m were operated stably and safe. (author)

Lightweight superconducting alternators

International Nuclear Information System (INIS)

Keim, T.A.

1988-01-01

One of the most efficient and most lightweight means of converting high-temperature heat energy to electricity is a turboalternator set. Turboalternators are potentially important components of burst-mode power systems, either chemical or nuclear powered. Also, they are probable key components in future electric propulsion systems. Existing examples of multimegawatt turbomachines have been optimized for a variety of aerospace uses, ranging from aircraft propulsion to rocket engine fuel pump drives. There is no corresponding history of multimegawatt alternators built to aerospace standards of mass, performance, and reliability. This paper discusses one of the few such development efforts presently in progress, and gives an indication of possible future potential. In large power ratings, superconducting generators offer substantial power density, specific weight, and efficiency advantages over competing technologies. A program at GE has led to the construction of a lightweight high-voltage 20-MW generator with a superconducting field winding. The first part of this paper describes the design of the generator. The second projects the capabilities of the generator to other ratings

Conventional proximity effect in bilayers of superconducting underdoped $La_{1.88}Sr_{0.12}CuO_4$ islands coated with non superconducting overdoped $La_{1.65}Sr_{0.35}CuO_4$

OpenAIRE

Koren, G.; Millo, O.

2009-01-01

Following a recent study by our group in which a large $T_c$ enhancement was reported in bilayers of the non-superconducting $La_{1.65}Sr_{0.35}CuO_4$ and superconducting $La_{1.88}Sr_{0.12}CuO_4$ films [Phys. Rev. Lett. \\textbf{101}, 057005 (2008)], we checked if a similar effect occurs when superconducting $La_{1.88}Sr_{0.12}CuO_4$ islands are coated with a continuous layer of the non superconducting $La_{1.65}Sr_{0.35}CuO_4$. We found that no such phenomenon is observed. The bare supercond...

Effect of superconducting correlation on the localization of quasiparticles in low dimensions

International Nuclear Information System (INIS)

Xiang, T.

1995-01-01

Localization lengths of superconducting quasiparticles λ s are evaluated and compared with the corresponding normal-state values λ n in one-dimensional (1D) and two-dimensional lattices. The effect of superconducting correlation on the localization of quasiparticles is generally stronger in an off-site pairing state than in an on-site pairing state. The modification of superconducting correlation to λ is strongly correlated with the density of states (DOS) of superconducting quasiparticles. λ s drops within the energy gap but is largely enhanced around energies where DOS peaks appear. For a gapless pairing state in 1D or a d-wave pairing state in 2D, λ s /λ n at the Fermi energy E F is of order 1 and determined purely by the value of gap parameter not by the random potential. For the d-wave pairing state, the localization effect is largely weakened compared with the corresponding normal state and quasiparticles with energies close to E F are more strongly localized than other low-energy quasiparticles

The progresses of superconducting technology for power grid last decade in China

Energy Technology Data Exchange (ETDEWEB)

Xiao, Liye; Gu, Hong Wei [Applied Superconductivity Laboratory, Chinese Academy of Sciences, Beijing (China)

2015-03-15

With the increasing development of renewable energy, it is expected that large-scale renewable power would be transported from the west and north area of China to the east and south area. For this reason, it will be necessary to develop a wide-area power grid in which the renewable energy would be the dominant power source, and the power grid will be faced by some critical challenges such as long-distance large-capacity power transmission, the stability of the wide-area power grid and the land use problem for the power grid. The superconducting technology for power (STP) would be a possible alternative for the development of China’s future power grid. In last decade, STP has been extensively developed in China. In this paper, we present an overview of the R and D of STP last decade in China including: 1) the development of high temperature superconducting (HTS) materials, 2) DC power cables, 3) superconducting power substations, 4) fault current limiters and 5) superconducting magnetic energy storage (SMES)

The progresses of superconducting technology for power grid last decade in China

International Nuclear Information System (INIS)

Xiao, Liye; Gu, Hong Wei

2015-01-01

With the increasing development of renewable energy, it is expected that large-scale renewable power would be transported from the west and north area of China to the east and south area. For this reason, it will be necessary to develop a wide-area power grid in which the renewable energy would be the dominant power source, and the power grid will be faced by some critical challenges such as long-distance large-capacity power transmission, the stability of the wide-area power grid and the land use problem for the power grid. The superconducting technology for power (STP) would be a possible alternative for the development of China’s future power grid. In last decade, STP has been extensively developed in China. In this paper, we present an overview of the R and D of STP last decade in China including: 1) the development of high temperature superconducting (HTS) materials, 2) DC power cables, 3) superconducting power substations, 4) fault current limiters and 5) superconducting magnetic energy storage (SMES)

Getting Hit by Pitch in Professional Baseball: Analysis of Injury Patterns, Risk Factors, Concussions, and Days Missed for Batters.

Science.gov (United States)

Camp, Christopher L; Wang, Dean; Sinatro, Alec S; D'Angelo, John; Coleman, Struan H; Dines, Joshua S; Fealy, Stephen; Conte, Stan

2018-05-01

Although batters are frequently hit by pitch (HBP) in baseball, the effect of HBP injuries remains undefined in the literature. To determine the effect of HBP injuries in terms of time out of play, injury patterns resulting in the greatest time out of play, and the value of protective gear such as helmets and elbow pads. Descriptive laboratory study. Based on the Major League Baseball (MLB) Health and Injury Tracking System, all injuries to batters HBP during the 2011-2015 MLB and Minor League Baseball (MiLB) seasons were identified and analyzed. Video analysis was performed on all HBP events from the 2015 MLB season. Multivariate stepwise regression analysis was utilized to determine the predictive capacity of multiple variables (velocity, pitch type, location, etc) on injury status and severity. A total of 2920 HBP injuries resulted in 24,624 days missed (DM) over the 5 seasons. MLB HBP injuries occurred at a rate of 1 per 2554 plate appearances (1 per 9780 pitches thrown). Mean DM per injury were 8.4 (11.7 for MLB vs 8.0 for MiLB, P hit in the head/face (odds ratio, 28.7) or distal upper extremity (odds ratio, 6.4) were more likely to be injured than players HBP in other locations. Players with an unprotected elbow missed 1.7 more days (95% CI, -4.1 to 7.6) than those with an elbow protector ( P = .554) when injured after being HBP. Although HBP injuries occur infrequently in the course of normal play, they collectively represent a significant source of time out of play. The most common body regions injured include the hands/fingers and head/face, and batters hit in these locations are significantly more likely to be injured. After contusions, concussions were the most common injury diagnosis.

Applications and fabrication processes of superconducting composite materials

International Nuclear Information System (INIS)

Gregory, E.

1984-01-01

This paper discusses the most recent applications and manufacturing considerations in the field of superconductivity. The constantly changing requirements of a growing number of users encourage development in fabrication and inspection techniques. For the first time, superconductors are being used commercially in large numbers and superconducting magnets are no longer just laboratory size. Although current demand for these conductors represents relatively small quantities of material, advances in the production of high-quality composites may accelerate technological growth into several new markets. Three large-scale application areas for superconductors are discussed: accelerator magnets for high-energy physics research, magnetic confinement for thermonuclear fusion, and magnetic resonance imaging for health care. Each application described is accompanied by a brief description of the conductors used and fabrication processes employed to make them

The g-2 storage ring superconducting magnet system

International Nuclear Information System (INIS)

Green, M.A.

1993-09-01

The g-2 μ lepton (muon) storage ring is a single dipole magnet that is 44 meters in circumference. The storage ring dipole field is created by three large superconducting solenoid coils. A single outer solenoid, 15.1 meters in diameter, carries 254 kA. Two inner solenoids, 13.4 meters in diameter, carry 127 kA each in opposition to the current carried by the outer solenoid. A room temperature C shaped iron yoke returns the magnetic flux and shapes the magnetic field in a 180 mm gap where the stored muon beam circulates. The gap induction will be 1.47 T. This report describes the three large superconducting solenoids, the cryogenic system needed to keep them cold, the solenoid power supply and the magnet quench protection system

Prediction of phonon-mediated superconductivity in hole-doped black phosphorus.

Science.gov (United States)

Feng, Yanqing; Sun, Hongyi; Sun, Junhui; Lu, Zhibin; You, Yong

2018-01-10

We study the conventional electron-phonon mediated superconducting properties of hole-doped black phosphorus by density functional calculations and get quite a large electron-phonon coupling (EPC) constant λ ~ 1.0 with transition temperature T C ~ 10 K, which is comparable to MgB 2 when holes are doped into the degenerate and nearly flat energy bands around the Fermi level. We predict that the softening of low-frequency [Formula: see text] optical mode and its phonon displacement, which breaks the lattice nonsymmorphic symmetry of gliding plane and lifts the band double degeneracy, lead to a large EPC. These factors are favorable for BCS superconductivity.

Prediction of phonon-mediated superconductivity in hole-doped black phosphorus

Science.gov (United States)

Feng, Yanqing; Sun, Hongyi; Sun, Junhui; Lu, Zhibin; You, Yong

2018-01-01

We study the conventional electron-phonon mediated superconducting properties of hole-doped black phosphorus by density functional calculations and get quite a large electron-phonon coupling (EPC) constant λ ~ 1.0 with transition temperature T C ~ 10 K, which is comparable to MgB2 when holes are doped into the degenerate and nearly flat energy bands around the Fermi level. We predict that the softening of low-frequency B3g1 optical mode and its phonon displacement, which breaks the lattice nonsymmorphic symmetry of gliding plane and lifts the band double degeneracy, lead to a large EPC. These factors are favorable for BCS superconductivity.

Thermal analysis of the cryocooled superconducting magnet for the liquid helium-free hybrid magnet

International Nuclear Information System (INIS)

Ishizuka, Masayuki; Hamajima, Takataro; Itou, Tomoyuki; Sakuraba, Junji; Nishijima, Gen; Awaji, Satoshi; Watanabe, Kazuo

2010-01-01

The liquid helium-free hybrid magnet, which consists of an outer large bore cryocooled superconducting magnet and an inner water-cooled resistive magnet, was developed for magneto-science in high fields. The characteristic features of the cryogen-free outsert superconducting magnet are described in detail in this paper. The superconducting magnet cooled by Gifford-McMahon cryocoolers, which has a 360 mm room temperature bore in diameter, was designed to generate high magnetic fields up to 10 T. The hybrid magnet has generated the magnetic field of 27.5 T by combining 8.5 T generation of the cryogen-free superconducting magnet with 19 T generation of the water-cooled resistive magnet. The superconducting magnet was composed of inner Nb 3 Sn coils and outer NbTi coils. In particular, inner Nb 3 Sn coils were wound using high-strength CuNi-NbTi/Nb 3 Sn wires in consideration of large hoop stress. Although the cryocooled outsert superconducting magnet achieved 9.5 T, we found that the outsert magnet has a thermal problem to generate the designed maximum field of 10 T in the hybrid magnet operation. This problem is associated with unexpected AC losses in Nb 3 Sn wires.

System considerations for airborne, high power superconducting generators

International Nuclear Information System (INIS)

Southall, H.L.; Oberly, C.E.

1979-01-01

The design of rotating superconducting field windings in high power generators is greatly influenced by system considerations. Experience with two superconducting generators designed to produce 5 and 20 Mw resulted in a number of design restrictions. The design restrictions imposed by system considerations have not prevented low weight and high voltage power generation capability. The application of multifilament Nb;sub 3;Sn has permitted a large thermal margin to be designed into the rotating field winding. This margin permits the field winding to remain superconducting under severe system operational requirements. System considerations include: fast rotational startup, fast ramped magnetic fields, load induced transient fields and airborne cryogen logistics. Preliminary selection of a multifilament Nb;sub 3;Sn cable has resulted from these considerations. The cable will carry 864 amp at 8.5K and 6.8 Tesla. 10 refs

Loss and Inductance Investigation in Superconducting Cable Conductors

DEFF Research Database (Denmark)

Olsen, Søren Krüger; Tønnesen, Ole; Træholt, Chresten

1999-01-01

An important parameter in the design and optimization of a superconducting cable conductor is the control of the current distribution among single tapes and layers. This distribution is to a large degree determined by inductances, since the resistances are low. The self and mutual inductances...... of transport current and current distribution.This presentation is based on a number of experiments performed on prototype superconducting cable conductors. The critical current (1uV/cm) of the conductor at 77K was 1590 A (cable #1) and 3240 A (cable #2) respectively.At an rms current of 2 kA (50 Hz) the AC......-loss was measured on cable #2 to 0.6W/mxphase. This is, to our knowledge, the lowest AC-loss (at 2kA and 77K) of a high temperature superconducting cable conductor reported so far....

Potential damage to dc superconducting magnets due to high frequency electromagnetic waves

Science.gov (United States)

Gabriel, G. J.; Burkhart, J. A.

1977-01-01

Studies of a d.c. superconducting magnet coil indicate that the large coil behaves as a straight waveguide structure. Voltages between layers within the coil sometimes exceeded those recorded at terminals where protective resistors are located. Protection of magnet coils against these excessive voltages could be accomplished by impedance matching throughout the coil system. The wave phenomenon associated with superconducting magnetic coils may create an instability capable of converting the energy of a quiescent d.c. superconducting coil into dissipative a.c. energy, even in cases when dielectric breakdown does not take place.

Hole superconductivity

International Nuclear Information System (INIS)

Hirsch, J.E.; Marsiglio, F.

1989-01-01

The authors review recent work on a mechanism proposed to explain high T c superconductivity in oxides as well as superconductivity of conventional materials. It is based on pairing of hole carriers through their direct Coulomb interaction, and gives rise to superconductivity because of the momentum dependence of the repulsive interaction in the solid state environment. In the regime of parameters appropriate for high T c oxides this mechanism leads to characteristic signatures that should be experimentally verifiable. In the regime of conventional superconductors most of these signatures become unobservable, but the characteristic dependence of T c on band filling survives. New features discussed her include the demonstration that superconductivity can result from repulsive interactions even if the gap function does not change sign and the inclusion of a self-energy correction to the hole propagator that reduces the range of band filling where T c is not zero

Emergent Higgsless Superconductivity

Directory of Open Access Journals (Sweden)

Cristina Diamantini M.

2017-01-01

Full Text Available We present a new Higgsless model of superconductivity, inspired from anyon superconductivity but P- and T-invariant and generalizable to any dimension. While the original anyon superconductivity mechanism was based on incompressible quantum Hall fluids as average field states, our mechanism involves topological insulators as average field states. In D space dimensions it involves a (D-1-form fictitious pseudovector gauge field which originates from the condensation of topological defects in compact lowenergy effective BF theories. There is no massive Higgs scalar as there is no local order parameter. When electromagnetism is switched on, the photon acquires mass by the topological BF mechanism. Although the charge of the gapless mode (2 and the topological order (4 are the same as those of the standard Higgs model, the two models of superconductivity are clearly different since the origins of the gap, reflected in the high-energy sectors are totally different. In 2D thi! s type of superconductivity is explicitly realized as global superconductivity in Josephson junction arrays. In 3D this model predicts a possible phase transition from topological insulators to Higgsless superconductors.

The quest for high-gradient superconducting cavities

International Nuclear Information System (INIS)

Padamsee, H.

1999-01-01

Superconducting RF cavities excel in applications requiring continuous waves or long pulse voltages. Since power losses in the walls of the cavity increase as the square of the accelerating voltage, copper cavities become uneconomical as demand for high continuous wave voltage grows with particle energy. For these reasons, RF superconductivity has become an important technology for high energy and high luminosity accelerators. The state of art in performance of sheet metal niobium cavities is best represented by the statistics of more than 300 5-cell, 1.5-GHz cavities built for CEBAF. Key aspects responsible for the outstanding performance of the CEBAF cavities set are the anti-multipactor, elliptical cell shape, good fabrication and welding techniques, high thermal conductivity niobium, and clean surface preparation. On average, field emission starts at the electric field of 8.7 MV/m, but there is a large spread, even though the cavities received nominally the same surface treatment and assembly procedures. In some cavities, field emission was detected as low as 3 MV/m. In others, it was found to be as high as 19 MV/m. As we will discuss, the reason for the large spread in the gradients is the large spread in emitter characteristics and the random occurrence of emitters on the surface. One important phenomenon that limits the achievable RF magnetic field is thermal breakdown of superconductivity, originating at sub-millimeter-size regions of high RF loss, called defects. Simulation reveal that if the defect is a normal conducting region of 200 mm radius, it will break down at 5 MV/m. Producing high gradients and high Q in superconducting cavities demands excellent control of material properties and surface cleanliness. The spread in gradients that arises from the random occurrence of defects and emitters must be reduced. It will be important to improve installation procedures to preserve the excellent gradients now obtained in laboratory test in vertical cryostats

Trends in Revision Elbow Ulnar Collateral Ligament Reconstruction in Professional Baseball Pitchers.

Science.gov (United States)

Wilson, Alexander T; Pidgeon, Tyler S; Morrell, Nathan T; DaSilva, Manuel F

2015-11-01

To determine the frequency of revision elbow ulnar collateral ligament (UCL) reconstruction in professional baseball pitchers. Data were collected on 271 professional baseball pitchers who underwent primary UCL reconstruction. Each player was evaluated retrospectively for occurrence of revision UCL reconstructive surgery to treat failed primary reconstruction. Data on players who underwent revision UCL reconstruction were compiled to determine total surgical revision incidence and revision rate by year. The incidence of early revision was analyzed for trends. Average career length after primary UCL reconstruction was calculated and compared with that of players who underwent revision surgery. Logistic regression analysis was performed to assess risk factors for revision including handedness, pitching role, and age at the time of primary reconstruction. Between 1974 and 2014, the annual incidence of primary UCL reconstructions among professional pitchers increased, while the proportion of cases being revised per year decreased. Of the 271 pitchers included in the study, 40 (15%) required at least 1 revision procedure during their playing career. Three cases required a second UCL revision reconstruction. The average time from primary surgery to revision was 5.2 ± 3.2 years (range, 1-13 years). The average length of career following primary reconstruction for all players was 4.9 ± 4.3 years (range, 0-22 years). The average length of career following revision UCL reconstruction was 2.5 ± 2.4 years (range, 0-8 years). No risk factors for needing revision UCL reconstruction were identified. The incidence of primary UCL reconstructions among professional pitchers is increasing; however, the rate of primary reconstructions requiring revision is decreasing. Explanations for the decreased revision rate may include improved surgical technique and improved rehabilitation protocols. Therapeutic IV. Copyright © 2015 American Society for Surgery of the Hand. Published by

Superconductive ceramics obtained with sol gel method

International Nuclear Information System (INIS)

Arcangeli, A.; Mosci, A.; Nardi, A.; Vatteroni, R.; Zondini, C.

1988-01-01

Several sol gel routes have been considered, studied and developed to produce large quantities of granulates which can be processed to obtain ceramics having good superconducting characteristics. In the considered process a mixture of commercial nitrates is atomized, at room temperature, in a solution 1:1 of Primene JMT and Benzene and a pale blue gel of the starting elements is suddently formed. The granulates obtained are free flowing, very reactive and well suited for pressing. For their intrinsic characteristics they could be very good precursors for the production of large quantities of superconductive ceramics in different forms. The precipitated gel is dried, calcinated, pressed in the form of cylindrical pellets which are sintered up to 960 degrees C. No griding or different thermal treatments are needed. The sintered material has low electric resistence, shows a clear Meissner effect and has a transition temperature of between 91 and 95 K

Superconducting quantum electronics

International Nuclear Information System (INIS)

Kose, V.

1989-01-01

This book reviews recent accomplishments, presents new results and discusses possible future developments of superconducting quantum electronics and high T c superconductivity. The three main parts of the book deal with fundamentals, sensitive detectors, and precision metrology. New results reported include: correct equivalent circuits modelling superconducting electronic devices; exact solution of the Mattis-Bardeen equations describing various experiments for thin films; complete theoretical description and experimental results for a new broad band spectrum analyzer; a new Josephson junction potentiometer allowing tracing of unknown voltage ratios back to well-known frequency ratios; and fast superconducting SQUID shift registers enabling the production of calculable noise power spectra in the microwave region

Radio frequency siliconization: An approach to the coating for the future large superconducting fusion devices

International Nuclear Information System (INIS)

Li, J.; Zhao, Y.P.; Wan, B.N.; Gong, X.Z.; Zhen, M.; Gu, X.M.; Zhang, X.D.; Luo, J.R.; Wan, Y.X.; Xie, J.K.; Li, C.F.; Chen, J.L.; Toi, K.; Noda, N.; Watari, T.

2001-01-01

Radio frequency (rf) siliconization has been carried out on the HT-7 superconducting tokamak in the presence of a high magnetic field, which is a try on superconducting tokamaks. Three different procedures of rf siliconization have been tested and a very promising method to produce high quality silicon films was found after comparing the film properties and plasma performance produced by these three different procedures. The Si/C films are amorphous, semitransparent, and homogeneous throughout the layer and adhere firmly to all the substrates. The advantages of silicon atoms as a powerful radiator and a good oxygen getter have been proved. An outstanding merit of rf siliconization to superconducting devices is its fast recovery after a serious degradation of the condition due to the leakage of air to good wall conditions. A wider stable operation region has been obtained and plasma performance is improved immediately after each siliconization due to significant reduction of impurities. Energy confinement time increases more than 50% and particle confinement time increases by a factor of 2. The lifetime of the silicon film is more than 400 standard ohmic heated plasma discharges. Simulation shows that the confinement improvement is due to the reduction of the electron thermal diffusivity in the outer region of the plasma

Investigation of wire motion in superconducting magnets

International Nuclear Information System (INIS)

Ogitsu, T.; Tsuchiya, K.; Devred, A.

1990-09-01

The large Lorentz forces occuring during the excitation of superconducting magnets can provoke sudden motions of wire, which eventually release enough energy to trigger a quench. These wire motions are accompanied by two electromagnetic effects: an induced emf along the moved wire, and a local change in flux caused by the minute dislocation of current. Both effects cause spikes in the coil voltage. Voltage data recorded during the excitation of a superconducting quadrupole magnet which early exhibit such events are here reported. Interpretations of the voltage spikes in terms of energy release are also presented, leading to insights on the spectrum of the disturbances which occur in real magnets. 15 refs

Upgrade of the protection system for superconducting circuits in the LHC

CERN Document Server

Denz, R; Formenti, F; Meß, K H; Siemko, A; Steckert, J; Walckiers, L; Strait, J

2010-01-01

Prior to the re-start of the Large Hadron Collider LHC in 2009 the protection system for superconducting magnets and bus-bars QPS will be substantially upgraded. The foreseen modifications will enhance the capability of the system in detecting problems related to the electrical interconnections between superconducting magnets as well as the detection of so-called aperture symmetric quenches in the LHC main magnets.

Upgrade of the protection system for superconducting circuits in the LHC

OpenAIRE

Denz, R; Dahlerup-Petersen, K; Formenti, F; Meß, K H; Siemko, A; Steckert, J; Walckiers, L; Strait, J

2009-01-01

Prior to the re-start of the Large Hadron Collider LHC in 2009 the protection system for superconducting magnets and bus-bars QPS will be substantially upgraded. The foreseen modifications will enhance the capability of the system in detecting problems related to the electrical interconnections between superconducting magnets as well as the detection of so-called aperture symmetric quenches in the LHC main magnets.

Superconductivity in graphite intercalation compounds

International Nuclear Information System (INIS)

Smith, Robert P.; Weller, Thomas E.; Howard, Christopher A.; Dean, Mark P.M.; Rahnejat, Kaveh C.; Saxena, Siddharth S.; Ellerby, Mark

2015-01-01

Highlights: • Historical background of graphite intercalates. • Superconductivity in graphite intercalates and its place in the field of superconductivity. • Recent developments. • Relevant modeling of superconductivity in graphite intercalates. • Interpretations that pertain and questions that remain. - Abstract: The field of superconductivity in the class of materials known as graphite intercalation compounds has a history dating back to the 1960s (Dresselhaus and Dresselhaus, 1981; Enoki et al., 2003). This paper recontextualizes the field in light of the discovery of superconductivity in CaC 6 and YbC 6 in 2005. In what follows, we outline the crystal structure and electronic structure of these and related compounds. We go on to experiments addressing the superconducting energy gap, lattice dynamics, pressure dependence, and how these relate to theoretical studies. The bulk of the evidence strongly supports a BCS superconducting state. However, important questions remain regarding which electronic states and phonon modes are most important for superconductivity, and whether current theoretical techniques can fully describe the dependence of the superconducting transition temperature on pressure and chemical composition

Superconductivity in graphite intercalation compounds

Energy Technology Data Exchange (ETDEWEB)

Smith, Robert P. [Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE (United Kingdom); Weller, Thomas E.; Howard, Christopher A. [Department of Physics & Astronomy, University College of London, Gower Street, London WCIE 6BT (United Kingdom); Dean, Mark P.M. [Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, NY 11973 (United States); Rahnejat, Kaveh C. [Department of Physics & Astronomy, University College of London, Gower Street, London WCIE 6BT (United Kingdom); Saxena, Siddharth S. [Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE (United Kingdom); Ellerby, Mark, E-mail: mark.ellerby@ucl.ac.uk [Department of Physics & Astronomy, University College of London, Gower Street, London WCIE 6BT (United Kingdom)

2015-07-15

Highlights: • Historical background of graphite intercalates. • Superconductivity in graphite intercalates and its place in the field of superconductivity. • Recent developments. • Relevant modeling of superconductivity in graphite intercalates. • Interpretations that pertain and questions that remain. - Abstract: The field of superconductivity in the class of materials known as graphite intercalation compounds has a history dating back to the 1960s (Dresselhaus and Dresselhaus, 1981; Enoki et al., 2003). This paper recontextualizes the field in light of the discovery of superconductivity in CaC{sub 6} and YbC{sub 6} in 2005. In what follows, we outline the crystal structure and electronic structure of these and related compounds. We go on to experiments addressing the superconducting energy gap, lattice dynamics, pressure dependence, and how these relate to theoretical studies. The bulk of the evidence strongly supports a BCS superconducting state. However, important questions remain regarding which electronic states and phonon modes are most important for superconductivity, and whether current theoretical techniques can fully describe the dependence of the superconducting transition temperature on pressure and chemical composition.

Overview on superconducting photoinjectors

CERN Document Server

Arnold, A

2011-01-01

The success of most of the proposed energy recovery linac (ERL) based electron accelerator projects for future storage ring replacements (SRR) and high power IR–free-electron lasers (FELs) largely depends on the development of an appropriate source. For example, to meet the FEL specifications [J.W. Lewellen, Proc. SPIE Int. Soc. Opt. Eng. 5534, 22 (2004)] electron beams with an unprecedented combination of high brightness, low emittance (0.1 µmrad), and high average current (hundreds of mA) are required. An elegant way to create a beam of such quality is to combine the high beam quality of a normal conducting rf photoinjector with the superconducting technology, i.e., to build a superconducting rf photoinjector (SRF gun). SRF gun R&D programs based on different approaches have been launched at a growing number of institutes and companies (AES, Beijing University, BESSY, BNL, DESY, FZD, TJNAF, Niowave, NPS, Wisconsin University). Substantial progress was achieved in recent years and the first long term ...

Magnetic levitation force between a superconducting bulk magnet and a permanent magnet

Energy Technology Data Exchange (ETDEWEB)

Wang, J J; He, C Y; Meng, L F; Li, C; Han, R S; Gao, Z X [Department of Physics, Key Laboratory for Artificial Microstructure and Mesoscopic Physics, Peking University, Beijing 100871 (China)

2003-04-01

The current density J({rho}, z) in a disc-shaped superconducting bulk magnet and the magnetic levitation force F{sup SBM}{sub z} exerted on the superconducting bulk magnet by a cylindrical permanent magnet are calculated from first principles. The effect of the superconducting parameters of the superconducting bulk is taken into account by assuming the voltage-current law E = E{sub c}(J/J{sub c}){sup n} and the material law B = {mu}{sub 0}H. The magnetic levitation force F{sup SBM}{sub z} is dominated by the remnant current density J'{sub 2}({rho}, z), which is induced by switching off the applied magnetizing field. High critical current density and flux creep exponent may increase the magnetic levitation force F{sup SBM}{sub z}. Large volume and high aspect ratio of the superconducting bulk can further enhance the magnetic levitation force F{sup SBM}{sub z}.

Mechanisms of conventional and high Tc superconductivity

International Nuclear Information System (INIS)

Kresin, V.L.; Morawitz, H.; Wolf, S.A.

1993-01-01

This book gives a careful and objective review of theories of superconductivity in traditional superconductors, organics, and high Tc cuprates. Of course, the authors do still present their own theories of cuprate superconductivity, but only in the final chapter after other possibilities have been discussed. The book should be especially useful for researchers entering the field of high Tc superconductivity. The reviews of photon mediated pairing and strong coupling theory are very welcome, since much of this material has not been reviewed since the classic 1969 volume edited by Parks. In particular the authors dispel the various myths that phonon mediated pairing leads to upper bounds on Tc. In addition to phonon mediated pairing the book discussed in detail pairing due to exchange of acoustic (demon) plasmons, excitons, or magnetic fluctuations. There have been so many diverse mechanisms based on strong correlation and large U Hubbard models that a book like this can only discuss a limited selection of the main contenders. In particular here the emphasis on Fermi liquid based models no doubt reflects the authors' own point of view. A whole chapter discusses the concepts of induced superconductivity, in the proximity effect, and its application to materials with several different electronic subsystems

Microscopic simulation model of superconducting transmission lines for standard microwave CAD programs

International Nuclear Information System (INIS)

Hoefer, G.J.; Kratz, H.A.

1993-01-01

Superconducting lines are very promising candidates for fast signal transmission in integrated circuits, because of their low losses and dispersion, which result in large usable bandwidths. Coplanar waveguides are of special interest, since only one superconducting layer is needed for their implementation. This requirement fits well the present day capabilities of the high temperature superconductor technology. At present, the major drawback of this type of transmission line is the lack of accurate and fast CAD models including the special properties of superconducting electrodes. In the following we will briefly describe the essentials of a model for the case of superconducting lines. For a complete description the reader is referenced to. The model has been proven to be useful in conjunction with commercially available microwave CAD programs. (orig.)

Technical tasks in superconducting cavities

Energy Technology Data Exchange (ETDEWEB)

Saito, Kenji [High Energy Accelerator Research Organization, Tsukuba, Ibaraki (Japan)

1997-11-01

The feature of superconducting rf cavities is an extremely small surface resistance on the wall. It brings a large energy saving in the operation, even those are cooled with liquid helium. That also makes possible to operate themselves in a higher field gradient comparing to normal conducting cavities, and brings to make accelerators compact. These merits are very important for the future accelerator engineering which is planed at JAERI for the neutron material science and nuclear waste transmutation. This machine is a high intensity proton linac and uses sc cavities in the medium and high {beta} sections. In this paper, starting R and D of proton superconducting cavities, several important technical points which come from the small surface resistance of sc cavities, are present to succeed it and also differences between the medium and high - {beta} structures are discussed. (author)

Comparison of 10 MW superconducting generator topologies for direct-drive wind turbines

DEFF Research Database (Denmark)

Liu, Dong; Polinder, Henk; Abrahamsen, Asger Bech

2015-01-01

Large wind turbines of 10 MW or higher power levels are desirable for reducing the cost of energy of offshore wind power conversion. Conventional wind generator systems will be costly if scaled up to 10 MW due to rather large size and weight. Direct drive superconducting generators have been...... magnetic field excitation allows for lightweight non-magnetic composite materials for machine cores instead of iron. A topology would probably not be a good option for an offshore wind turbine generator if it demands a far more expensive active material cost than others, even if it has other advantages...... proposed to address the problem with generator size, because the electrical machines with superconducting windings are capable of achieving a higher torque density of an electrical machine. However, the topology to be adopted for superconducting wind generators has not yet been settled, since the high...

Results of the international Large Coil Task: a milestone for superconducting magnets in fusion power

International Nuclear Information System (INIS)

Dresner, L.; Fietz, W.A.; Gauss, S.

1989-01-01

The aim of the Large Coil Task (LCT) was to demonstrate the reliable operation of large superconducting toroidal field coils and to prove the design principles and fabrication techniques to be applied for the magnets in a tokamak experimental power reactor. This has been achieved by an international development effort involving the US DOE, EURATOM, JAERI and the Swiss government. Six different D-shaped test coils were separately designed, developed and constructed by the LCT participants, then extensively tested together in a compact toroidal array. Detailed information on coil design and manufacture and all test data were shared among the LCT participants. The full six-coil array tests were carried out in a continuous period from the beginning of 1986 until September 1987. Beside the originally planned tests to reach an 8 T design point performance, the tests went well beyond this goal, reaching 9 T peak field in each coil. The experiments also delineated the limits of operability and demonstrated the coil safety under abnormal conditions. For fusion application the transient a.c. field behaviour in the coils was also of great interest. Three of the coils have been tested in this respect and showed excellent performance, with loss values in agreement with the theoretical predictions. (author)

Detailed design of the large-bore 8 T superconducting magnet for the NAFASSY test facility

Science.gov (United States)

Corato, V.; Affinito, L.; Anemona, A.; Besi Vetrella, U.; Di Zenobio, A.; Fiamozzi Zignani, C.; Freda, R.; Messina, G.; Muzzi, L.; Perrella, M.; Reccia, L.; Tomassetti, G.; Turtù, S.; della Corte, A.

2015-03-01

The ‘NAFASSY’ (NAtional FAcility for Superconducting SYstems) facility is designed to test wound conductor samples under high-field conditions at variable temperatures. Due to its unique features, it is reasonable to assume that in the near future NAFASSY will have a preeminent role at the international level in the qualification of long coiled cables in operative conditions. The magnetic system consists of a large warm bore background solenoid, made up of three series-connected grading sections obtained by winding three different Nb3Sn Cable-in-Conduit Conductors. Thanks to the financial support of the Italian Ministry for University and Research the low-field coil is currently under production. The design has been properly modified to allow the system to operate also as a stand-alone facility, with an inner bore diameter of 1144 mm. This magnet is able to provide about 7 T on its axis and about 8 T close to the insert inner radius, giving the possibility of performing a test relevant for large-sized NbTi or medium-field Nb3Sn conductors. The detailed design of the 8 T magnet, including the electro-magnetic, structural and thermo-hydraulic analysis, is here reported, as well as the production status.

Modern high-temperature superconductivity

International Nuclear Information System (INIS)

Ching Wu Chu

1988-01-01

Ever since the discovery of superconductivity in 1911, its unusual scientific challenge and great technological potential have been recognized. For the past three-quarters of a century, superconductivity has done well on the science front. This is because sueprconductivity is interesting not only just in its own right but also in its ability to act as a probe to many exciting nonsuperconducting phenomena. For instance, it has continued to provide bases for vigorous activities in condensed matter science. Among the more recent examples are heavy-fermion systems and organic superconductors. During this same period of time, superconductivity has also performed admirably in the applied area. Many ideas have been conceived and tested, making use of the unique characteristics of superconductivity - zero resistivity, quantum interference phenomena, and the Meissner effect. In fact, it was not until late January 1987 that it became possible to achieve superconductivity with the mere use of liquid nitrogen - which is plentiful, cheap, efficient, and easy to handle - following the discovery of supercondictivity above 90 K in Y-Ba-Cu-O, the first genuine quaternary superconductor. Superconductivity above 90 K poses scientific and technological challenges not previously encountered: no existing theories can adequately describe superconductivity above 40 K and no known techniques can economically process the materials for full-scale applications. In this paper, therefore, the author recalls a few events leading to the discovery of the new class of quaternary compounds with a superconducting transition temperature T c in the 90 K range, describes the current experimental status of high-temperature superconductivity and, finally, discusses the prospect of very-high-temperature superconductivity, i.e., with a T c substantially higher than 100 K. 97 refs., 7 figs

Inhomogeneous superconductivity in a ferromagnet

International Nuclear Information System (INIS)

Kontos, T.; Aprili, M.; Lesueur, J.; Genet, F.; Boursier, R.; Grison, X.

2003-01-01

We have studied a new superconducting state where the condensate wave function resulting from conventional pairing, is modified by an exchange field. Superconductivity is induced into a ferromagnetic thin film (F) by the proximity effect with a superconducting reservoir (S). We observed oscillations of the superconducting order parameter induced in F as a function of the distance from the S/F interface. They originate from the finite momentum transfer provided to Cooper pairs by the splitting of the spin up and down bands. We measured the superconducting density of states in F by tunneling spectroscopy and the Josephson critical current when F is coupled with a superconducting counter-electrode. Negative values of the superconducting order parameter are revealed by capsized tunneling spectra in F and a negative Josephson coupling (π-junction)

Local switching of two-dimensional superconductivity using the ferroelectric field effect

Science.gov (United States)

Takahashi, K. S.; Gabay, M.; Jaccard, D.; Shibuya, K.; Ohnishi, T.; Lippmaa, M.; Triscone, J.-M.

2006-05-01

Correlated oxides display a variety of extraordinary physical properties including high-temperature superconductivity and colossal magnetoresistance. In these materials, strong electronic correlations often lead to competing ground states that are sensitive to many parameters-in particular the doping level-so that complex phase diagrams are observed. A flexible way to explore the role of doping is to tune the electron or hole concentration with electric fields, as is done in standard semiconductor field effect transistors. Here we demonstrate a model oxide system based on high-quality heterostructures in which the ferroelectric field effect approach can be studied. We use a single-crystal film of the perovskite superconductor Nb-doped SrTiO3 as the superconducting channel and ferroelectric Pb(Zr,Ti)O3 as the gate oxide. Atomic force microscopy is used to locally reverse the ferroelectric polarization, thus inducing large resistivity and carrier modulations, resulting in a clear shift in the superconducting critical temperature. Field-induced switching from the normal state to the (zero resistance) superconducting state was achieved at a well-defined temperature. This unique system could lead to a field of research in which devices are realized by locally defining in the same material superconducting and normal regions with `perfect' interfaces, the interface being purely electronic. Using this approach, one could potentially design one-dimensional superconducting wires, superconducting rings and junctions, superconducting quantum interference devices (SQUIDs) or arrays of pinning centres.

Comparing superconducting and permanent magnets for magnetic refrigeration

Directory of Open Access Journals (Sweden)

R. Bjørk

2016-05-01

Full Text Available We compare the cost of a high temperature superconducting (SC tape-based solenoid with a permanent magnet (PM Halbach cylinder for magnetic refrigeration. Assuming a five liter active magnetic regenerator volume, the price of each type of magnet is determined as a function of aspect ratio of the regenerator and desired internal magnetic field. It is shown that to produce a 1 T internal field in the regenerator a permanent magnet of hundreds of kilograms is needed or an area of superconducting tape of tens of square meters. The cost of cooling the SC solenoid is shown to be a small fraction of the cost of the SC tape. Assuming a cost of the SC tape of 6000 $/m2 and a price of the permanent magnet of 100 $/kg, the superconducting solenoid is shown to be a factor of 0.3-3 times more expensive than the permanent magnet, for a desired field from 0.5-1.75 T and the geometrical aspect ratio of the regenerator. This factor decreases for increasing field strength, indicating that the superconducting solenoid could be suitable for high field, large cooling power applications.

Parallel magnetic field suppresses dissipation in superconducting nanostrips

Energy Technology Data Exchange (ETDEWEB)

Wang, Yong-Lei; Glatz, Andreas; Kimmel, Gregory J.; Aranson, Igor S.; Thoutam, Laxman R.; Xiao, Zhi-Li; Berdiyorov, Golibjon R.; Peeters, François M.; Crabtree, George W.; Kwok, Wai-Kwong

2017-11-13

The motion of Abrikosov vortices in type-II superconductors results in a finite resistance in the presence of an applied electric current. Elimination or reduction of the resistance via immobilization of vortices is the "holy grail" of superconductivity research. Common wisdom dictates that an increase in the magnetic field escalates the loss of energy since the number of vortices increases. Here we show that this is no longer true if the magnetic field and the current are applied parallel to each other. Our experimental studies on the resistive behavior of a superconducting Mo0.79Ge0.21 nanostrip reveal the emergence of a dissipative state with increasing magnetic field, followed by a pronounced resistance drop, signifying a reentrance to the superconducting state. Large-scale simulations of the 3D time-dependent Ginzburg-Landau model indicate that the intermediate resistive state is due to an unwinding of twisted vortices. When the magnetic field increases, this instability is suppressed due to a better accommodation of the vortex lattice to the pinning configuration. Our findings show that magnetic field and geometrical confinement can suppress the dissipation induced by vortex motion and thus radically improve the performance of superconducting materials.

Parallel magnetic field suppresses dissipation in superconducting nanostrips.

Science.gov (United States)

Wang, Yong-Lei; Glatz, Andreas; Kimmel, Gregory J; Aranson, Igor S; Thoutam, Laxman R; Xiao, Zhi-Li; Berdiyorov, Golibjon R; Peeters, François M; Crabtree, George W; Kwok, Wai-Kwong

2017-11-28

The motion of Abrikosov vortices in type-II superconductors results in a finite resistance in the presence of an applied electric current. Elimination or reduction of the resistance via immobilization of vortices is the "holy grail" of superconductivity research. Common wisdom dictates that an increase in the magnetic field escalates the loss of energy since the number of vortices increases. Here we show that this is no longer true if the magnetic field and the current are applied parallel to each other. Our experimental studies on the resistive behavior of a superconducting Mo 0.79 Ge 0.21 nanostrip reveal the emergence of a dissipative state with increasing magnetic field, followed by a pronounced resistance drop, signifying a reentrance to the superconducting state. Large-scale simulations of the 3D time-dependent Ginzburg-Landau model indicate that the intermediate resistive state is due to an unwinding of twisted vortices. When the magnetic field increases, this instability is suppressed due to a better accommodation of the vortex lattice to the pinning configuration. Our findings show that magnetic field and geometrical confinement can suppress the dissipation induced by vortex motion and thus radically improve the performance of superconducting materials.

Progress on the superconducting magnet for the time projection chamber experiment (TPC) at PEP

International Nuclear Information System (INIS)

Green, M.A.; Eberhard, P.H.; Burns, W.A.

1980-01-01

The TPC (Time Projection Chamber) experiment at PEP will have a two meter inside diameter superconducting magnet which creatests a 1.5 T uniform solenoidal field for the TPC. The superconducting magnet coil, cryostat, cooling system, and the TPC gas pressure vessel (which operatests at 11 atm) were designed to be about two thirds of a radiation length thick. As a result, a high current density coil design was chosen. The magnet is cooled by forced flow two phase helium. The TPC magnet is the largest adiabatically stable superconducting magnet built to date. The paper presents the parameters of the TPC thin solenoid and its subsystems. Tests results from the Spring 1980 cryogenic tes are presented. The topics to be dealt with in the paper are cryogenic services and the tests of magnet subsystems such as the folded current leads. Large thin superconducting magnet technology will be important to large detectors to be used on LEP

Mortality of major league baseball players from Canada, Latin America, and the Caribbean

Directory of Open Access Journals (Sweden)

Robert J. Reynolds

2012-07-01

Full Text Available Professional baseball players have lower mortality rates than the US general population, but whether this is true of foreign-born players is not known. Using data on ballplayers from six nations, we compare mortality rates with those of US players via standardized mortality ratios. After controlling for confounders, four countries had statistically insignificant SMRs while two nations had significantly elevated SMRs. In the two nations with elevated SMRs, low average ages at death and high crime rates suggest the increased mortality may be linked to violent crime. A full understanding of the causes of disparity in mortality will require further research.

Mortality of major league baseball players from Canada, Latin America, and the Caribbean

Directory of Open Access Journals (Sweden)

Robert J. Reynolds

2012-01-01

Full Text Available Professional baseball players have lower mortality rates than the US general population, but whether this is true of foreign-born players is not known. Using data on ballplayers from six nations, we compare mortality rates with those of US players via standardized mortality ratios. After controlling for confounders, four countries had statistically insignificant SMRs while two nations had significantly elevated SMRs. In the two nations with elevated SMRs, low average ages at death and high crime rates suggest the increased mortality may be linked to violent crime. A full understanding of the causes of disparity in mortality will require further research.

d-wave superconductivity in the frustrated two-dimensional periodic Anderson model

Directory of Open Access Journals (Sweden)

Wei Wu

2015-02-01

Full Text Available Superconductivity in heavy-fermion materials can sometimes appear in the incoherent regime and in proximity to an antiferromagnetic quantum critical point. Here, we study these phenomena using large-scale determinant quantum Monte Carlo simulations and the dynamical cluster approximation with various impurity solvers for the periodic Anderson model with frustrated hybridization. We obtain solid evidence for a d_{x^{2}−y^{2}} superconducting phase arising from an incoherent normal state in the vicinity of an antiferromagnetic quantum critical point. There is a coexistence region, and the width of the superconducting dome increases with frustration. Through a study of the pairing dynamics, we find that the retarded spin fluctuations give the main contribution to the pairing glue. These results are relevant for unconventional superconductivity in the Ce-115 family of heavy fermions.

Design, Fabrication and Initial Testing of a Large Bore Single Aperture 1 m Long Superconducting Dipole Made with Phenolic Inserts

CERN Document Server

Boschmann, H; Kirby, G A; Lucas, J; Ostojic, R; Russenschuck, Stephan; Siemko, A; Vanenkov, I; Weterings, W

1997-01-01

In the framework of the LHC magnet development programme, a large bore single aperture 1-meter long superconducting dipole has been built in collaboration with HOLEC. The magnet features a single layer coil wound using the LHC main dipole outer layer cable, phenolic inserts, and a keyed two part structural iron yoke. This paper presents the magnetic and mechanical design and optimisation of the magnet. We describe the coil winding and curing, and present the construction and assembly procedures. Finally we report on the mechanical behaviour during assembly and cooling, and present the magnet training behaviour.

WORKSHOP: Radiofrequency superconductivity

Energy Technology Data Exchange (ETDEWEB)

Anon.

1984-10-15

The Second Workshop on Radiofrequency Superconductivity was held at CERN from 23-27 July, four years after the first, organized at Karlsruhe. 35 invited talks were presented to the about 80 participants from Australia, Brazil, Europe, Japan and the United States. For the first time, ten Laboratories operating or planning superconducting accelerators for heavy ions participated and shared their experience with the community proposing the use of superconducting accelerating sections for electron accelerators.

WORKSHOP: Radiofrequency superconductivity

International Nuclear Information System (INIS)

Anon.

1984-01-01

The Second Workshop on Radiofrequency Superconductivity was held at CERN from 23-27 July, four years after the first, organized at Karlsruhe. 35 invited talks were presented to the about 80 participants from Australia, Brazil, Europe, Japan and the United States. For the first time, ten Laboratories operating or planning superconducting accelerators for heavy ions participated and shared their experience with the community proposing the use of superconducting accelerating sections for electron accelerators

Electronic Systems for the Protection of Superconducting Devices in the LHC

CERN Document Server

Denz, R; Mess, K H

2008-01-01

The Large Hadron Collider LHC [1] incorporates an unprecedented amount of superconducting components: magnets, bus-bars, and current leads. Most of them require active protection in case of a transition from the superconducting to the resistive state, the so-called quench. The electronic systems ensuring the reliable quench detection and further protection of these devices have been developed and produced over the last years and are currently being put into operation

Modal bifurcation in a high-Tc superconducting levitation system

International Nuclear Information System (INIS)

Taguchi, D; Fujiwara, S; Sugiura, T

2011-01-01

This paper deals with modal bifurcation of a multi-degree-of-freedom high-T c superconducting levitation system. As modeling of large-scale high-T c superconducting levitation applications, where plural superconducting bulks are often used, it can be helpful to consider a system constituting of multiple oscillators magnetically coupled with each other. This paper investigates nonlinear dynamics of two permanent magnets levitated above high-T c superconducting bulks and placed between two fixed permanent magnets without contact. First, the nonlinear equations of motion of the levitated magnets were derived. Then the method of averaging was applied to them. It can be found from the obtained solutions that this nonlinear two degree-of-freedom system can have two asymmetric modes, in addition to a symmetric mode and an antisymmetric mode both of which also exist in the linearized system. One of the backbone curves in the frequency response shows a modal bifurcation where the two stable asymmetric modes mentioned above appear with destabilization of the antisymmetric mode, thus leading to modal localization. These analytical predictions have been confirmed in our numerical analysis and experiments of free vibration and forced vibration. These results, never predicted by linear analysis, can be important for application of high-T c superconducting levitation systems.

Process for producing clad superconductive materials

International Nuclear Information System (INIS)

Cass, R.B.; Ott, K.C.; Peterson, D.E.

1992-01-01

This patent describes a process for fabricating superconducting composite wire. It comprises placing a superconductive precursor admixture capable of undergoing self propagating combustion in stoichiometric amounts sufficient to form a superconductive product within an oxygen-porous metal tube; sealing one end of the tube; igniting the superconductive precursor admixture whereby the superconductive precursor admixture endburns along the length of the admixture; and cross-section reducing the tube at a rate substantially equal to the rate of burning of the superconductive precursor admixture and at a point substantially planar with the burnfront of the superconductive precursor mixture, whereby a clad superconductive product is formed in situ

Decay and snapback in superconducting accelerator magnets

NARCIS (Netherlands)

Haverkamp, M.

2003-01-01

This thesis deals with the explanation and compensation of the effects ‘decay’ and ‘snapback’ in superconducting accelerator magnets, in particular in those used in the new Large Hardron Collider at CERN. During periods of constant magnet excitation, as for example during the injection of particles

Behaviour of large cylindrical drift chambers in a superconducting solenoid

International Nuclear Information System (INIS)

Boer, W. de; Fues, W.; Grindhammer, G.; Kotthaus, R.; Lierl, H.; Moss, L.

1980-04-01

We describe the construction and behaviour of a set of cylindrical drift chambers operating inside a superconducting solenoid with a central magnetic field of 1.3 T. The chambers are part of the 4 π detector CELLO at the e + e - storage ring PETRA in Hamburg. The chambers were designed without field shaping to keep them as simple as possible. In order to parametrize accurately the nonlinear space-time relation, we used a computer simulation of the drift process in inhomogenous electric and magnetic fields. With such a parametrization we achieved a resolution of 210 μm, averaged over the whole drift cell and angles of incidence up to 30 0 . (orig.)

Capacitor energy needed to induce transitions from the superconducting to the normal state

International Nuclear Information System (INIS)

Eberhard, P.H.; Ross, R.R.

1985-08-01

The purpose of this paper is to describe a technique to turn a long length of superconducting wire normal by dumping a charged capacitor into it and justify some formulae needed in the design. The physical phenomenon is described. A formula for the energy to be stored in the capacitor is given. There are circumstances where the dc in an electrical circuit containing superconducting elements has to be turned off quickly and where the most convenient way to switch the current off is to turn a large portion or all of the superconducting wire normal. Such was the case of the Time Projection Chamber (TPC) superconducting magnet as soon as a quench was detected. The technique used was the discharge of a capacitor into the coil center tap. It turned the magnet winding normal in ten milliseconds or so and provided an adequate quench protection. The technique of discharging a capacitor into a superconducting wire should have many other applications whenever a substantial resistance in a superconducting circuit has to be generated in that kind of time scale. The process involves generating a pulse of large currents in some part of the circuit and heating the wire up by ac losses until the value of the wire critical current is smaller than the dc current. Use of low inductance connections to the circuit is necessary. Then the dc gets turned off due to the resistance of the wire as in a magnet quench

Analysis of flat rolling of superconducting silver/ceramic composites

DEFF Research Database (Denmark)

Bech, Jakob Ilsted; Nielsen, Morten Storgård; Eriksen, Morten

2001-01-01

The flat rolling process from wire to tape is presumably the most crucial link in the chain of mechanical processes leading from loose powder and silver tubes to the final superconducting Ag/BSCCO tape. In order to improve the critical current density of the superconducting filaments, one must...... process these to the highest possible density without at the same time introducing failures as large cracks and macroscopic shear bands. In order to analyse and optimise the process, the interaction between the involved materials and their very different mechanical properties must be taken into account...

A chopper circuit for energy transfer between superconducting magnets

International Nuclear Information System (INIS)

Onishi, Toshitada; Tateishi, Hiroshi; Takeda, Masatoshi; Matsuura, Toshiaki; Nakatani, Toshio.

1986-01-01

It has been suggested that superconducting magnets could provide a medium for storing energy and supplying the large energy pulses needed by experimental nuclear-fusion equipment and similar loads. Based on this concept, tests on energy transfer between superconducting magnets are currently being conducted at the Agency of Industrial Science and Technology's Electrotechnical Laboratory. Mitsubishi Electric has pioneered the world's first chopper circuit for this application. The circuit has the advantages of being simple and permitting high-speed, bipolar energy transfer. The article describes this circuit and its testing. (author)

Superconducting Wind Turbine Generators

Directory of Open Access Journals (Sweden)

Yunying Pan

2016-08-01

Full Text Available Wind energy is well known as a renewable energy because its clean and less polluted characteristic, which is the foundation of development modern wind electricity. To find more efficient wind turbine is the focus of scientists around the world. Compared from conventional wind turbines, superconducting wind turbine generators have advantages at zero resistance, smaller size and lighter weight. Superconducting wind turbine will inevitably become the main trends in this area. This paper intends to introduce the basic concept and principle of superconductivity, and compare form traditional wind turbine to obtain superiority, then to summary three proposed machine concept.While superconductivity have difficulty  in modern technology and we also have proposed some challenges in achieving superconducting wind turbine finally.

Superconducting cermets

International Nuclear Information System (INIS)

Goyal, A.; Funkenbusch, P.D.; Chang, G.C.S.; Burns, S.J.

1988-01-01

Two distant classes of superconducting cermets can be distinguished, depending on whether or not a fully superconducting skeleton is established. Both types of cermets have been successfully fabricated using non-noble metals, with as high as 60wt% of the metal phase. The electrical, magnetic and mechanical behavior of these composites is discussed

« Nous sommes tous frères ». Les valeurs des Elephants de Brother, club de baseball professionnel à Taiwan “We are all Brothers”. The Values of Brother Elephants, professional baseball club in Taiwan

Directory of Open Access Journals (Sweden)

Jérôme Soldani

2013-06-01

Full Text Available À Taiwan, où le baseball est considéré comme le « sport national », les équipes professionnelles sont la propriété de grandes firmes locales et ne sont pas formellement attachées à une municipalité. Ce sont elles-mêmes de petites entreprises qui proposent, en archétype de société, un mode de fonctionnement interne qui repose sur des valeurs autour desquelles se fédèrent leurs supporters. Basée sur une enquête ethnographique de douze mois, notamment au sein de la formation professionnelle des Elephants de Brother, cette contribution montrera comment celle-ci se donne à voir comme une entreprise structurée autour de valeurs morales entendues comme « traditionnelles » et dont les joueurs de l’équipe sont érigés en parangons. Le modèle d’une famille unie et strictement hiérarchisée est mis en exergue par les propriétaires du club et son iconographie. Mais ces représentations se heurtent à la réalité de la pratique quotidienne et aux affaires de corruption qui sapent régulièrement l’image de la ligue professionnelle taiwanaise.In Taiwan, where baseball is considered as the national sport, professional teams are owned by large local firms and are not formally attached to a municipality. They are themselves small companies offering an archetypal society, whose mode of internal operations are based on values around which to unite their fans. Based on an ethnographic study of twelve months, particularly among the professional team of Brother Elephants, this contribution will show how it is to be seen as an enterprise structured around moral values understood as traditional and whose players are established as paragons. The model of a united family and strictly hierarchical is highlighted by the owners of the club and its iconography. But these representations are faced with the reality of daily practice and corruption that regularly undermine the image of the Taiwanese professional league.

Superconducting magnets advanced in particle physics

International Nuclear Information System (INIS)

Yamamoto, Akira

2000-01-01

Superconducting magnet technology for particle detectors has been advanced to provide large-scale magnetic fields in particle physics experiments. The technology has been progressed to meet physics goals and the detector requirement of having maximum magnetic field with minimum material and space. This paper includes an overview of the advances of particle detector magnets and discusses key technologies

Rf superconducting devices

International Nuclear Information System (INIS)

Hartwig, W.H.; Passow, C.

1975-01-01

Topics discussed include (1) the theory of superconductors in high-frequency fields (London surface impedance, anomalous normal surface resistance, pippard nonlocal theory, quantum mechanical model, superconductor parameters, quantum mechanical calculation techniques for the surface, impedance, and experimental verification of surface impedance theories); (2) residual resistance (separation of losses, magnetic field effects, surface resistance of imperfect and impure conductors, residual loss due to acoustic coupling, losses from nonideal surfaces, high magnetic field losses, field emission, and nonlinear effects); (3) design and performance of superconducting devices (design considerations, materials and fabrication techniques, measurement of performance, and frequency stability); (4) devices for particle acceleration and deflection (advantages and problems of using superconductors, accelerators for fast particles, accelerators for particles with slow velocities, beam optical devices separators, and applications and projects under way); (5) applications of low-power superconducting resonators (superconducting filters and tuners, oscillators and detectors, mixers and amplifiers, antennas and output tanks, superconducting resonators for materials research, and radiation detection with loaded superconducting resonators); and (6) transmission and delay lines

Superconducting Ferromagnetic Nanodiamond.

Science.gov (United States)

Zhang, Gufei; Samuely, Tomas; Xu, Zheng; Jochum, Johanna K; Volodin, Alexander; Zhou, Shengqiang; May, Paul W; Onufriienko, Oleksandr; Kačmarčík, Jozef; Steele, Julian A; Li, Jun; Vanacken, Johan; Vacík, Jiri; Szabó, Pavol; Yuan, Haifeng; Roeffaers, Maarten B J; Cerbu, Dorin; Samuely, Peter; Hofkens, Johan; Moshchalkov, Victor V

2017-06-27

Superconductivity and ferromagnetism are two mutually antagonistic states in condensed matter. Research on the interplay between these two competing orderings sheds light not only on the cause of various quantum phenomena in strongly correlated systems but also on the general mechanism of superconductivity. Here we report on the observation of the electronic entanglement between superconducting and ferromagnetic states in hydrogenated boron-doped nanodiamond films, which have a superconducting transition temperature T c ∼ 3 K and a Curie temperature T Curie > 400 K. In spite of the high T Curie , our nanodiamond films demonstrate a decrease in the temperature dependence of magnetization below 100 K, in correspondence to an increase in the temperature dependence of resistivity. These anomalous magnetic and electrical transport properties reveal the presence of an intriguing precursor phase, in which spin fluctuations intervene as a result of the interplay between the two antagonistic states. Furthermore, the observations of high-temperature ferromagnetism, giant positive magnetoresistance, and anomalous Hall effect bring attention to the potential applications of our superconducting ferromagnetic nanodiamond films in magnetoelectronics, spintronics, and magnetic field sensing.

Testimony of the Council on Superconductivity for American Competitiveness before Texas A and M University

International Nuclear Information System (INIS)

Ott, K.D.

1988-01-01

The Council on Superconductivity for American Competitiveness (CSAC) is a private, non-profit association of small and large American corporations, as well as universities, research institutes, national laboratories and individuals concerned with the emerging technological and commercial potential of superconductivity. CSAC's purpose is to both educate and inform its members of developments in the laboratory, the entrepreneurial sector, the U.S. Congress and the Federal agencies that may have a bearing on the ultimate competitive posture of this nation as we proceed to the realm of device commercialization utilizing superconductivity as a technology base. This paper present CSAC's report on superconductivity

The Physics of Superconducting Microwave Resonators

Science.gov (United States)

Gao, Jiansong

Over the past decade, low temperature detectors have brought astronomers revolutionary new observational capabilities and led to many great discoveries. Although a single low temperature detector has very impressive sensitivity, a large detector array would be much more powerful and are highly demanded for the study of more difficult and fundamental problems in astronomy. However, current detector technologies, such as transition edge sensors and superconducting tunnel junction detectors, are difficult to integrate into a large array. The microwave kinetic inductance detector (MKID) is a promising new detector technology invented at Caltech and JPL which provides both high sensitivity and an easy solution to the detector integration. It senses the change in the surface impedance of a superconductor as incoming photons break Cooper pairs, by using high-Q superconducting microwave resonators capacitively coupled to a common feedline. This architecture allows thousands of detectors to be easily integrated through passive frequency domain multiplexing. In this thesis, we explore the rich and interesting physics behind these superconducting microwave resonators. The first part of the thesis discusses the surface impedance of a superconductor, the kinetic inductance of a superconducting coplanar waveguide, and the circuit response of a resonator. These topics are related with the responsivity of MKIDs. The second part presents the study of the excess frequency noise that is universally observed in these resonators. The properties of the excess noise, including power, temperature, material, and geometry dependence, have been quantified. The noise source has been identified to be the two-level systems in the dielectric material on the surface of the resonator. A semi-empirical noise model has been developed to explain the power and geometry dependence of the noise, which is useful to predict the noise for a specified resonator geometry. The detailed physical noise